FINITE ELEMENT ANALYSIS FOR CHIP FORMATION IN HIGH SPEED TURNING OPERATIONS BY ARBITRARY LAGRANG
石墨片作辅助热沉的高功率半导体激光器热传导特性
第４０卷㊀第７期２０１９年７月发㊀光㊀学㊀报ＣＨＩＮＥＳＥＪＯＵＲＮＡＬＯＦＬＵＭＩＮＥＳＣＥＮＣＥＶｏｌ ４０Ｎｏ ７Ｊｕｌｙꎬ２０１９文章编号:１０００￣７０３２(２０１９)０７￣０９０７￣０８石墨片作辅助热沉的高功率半导体激光器热传导特性房俊宇ꎬ石琳琳∗ꎬ张㊀贺ꎬ杨智焜ꎬ徐英添ꎬ徐㊀莉ꎬ马晓辉(长春理工大学高功率半导体激光国家重点实验室ꎬ吉林长春㊀１３００２２)摘要:为使边发射高功率单管半导体激光器有源区温度降低ꎬ增加封装结构的散热性能ꎬ降低器件封装成本ꎬ提出一种采用高热导率的石墨片作为辅助热沉的高功率半导体激光器封装结构ꎮ利用有限元分析研究了采用石墨片作辅助热沉后ꎬ封装器件的工作热阻更低ꎬ散热效果更好ꎮ研究分析过渡热沉铜钨合金与辅助热沉石墨的宽度尺寸变化对半导体激光器有源区温度的影响ꎮ新型封装结构与使用铜钨合金作为过渡热沉的传统结构相比ꎬ有源区结温降低４.５Ｋꎬ热阻降低０.４５Ｋ/Ｗꎮ通过计算可知ꎬ激光器的最大输出功率为２０.６Ｗꎮ在研究结果的指导下ꎬ确定铜钨合金与石墨的结构尺寸ꎬ以达到最好的散热效果ꎮ关㊀键㊀词:半导体激光器ꎻ散热性能ꎻ石墨辅助热沉ꎻ有限元分析ꎻ封装结构中图分类号:ＴＮ２４８㊀㊀㊀文献标识码:Ａ㊀㊀㊀ＤＯＩ:１０.３７８８/ｆｇｘｂ２０１９４００７.０９０７ＨｅａｔＴｒａｎｓｆｅｒＣｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆＨｉｇｈＰｏｗｅｒＳｅｍｉｃｏｎｄｕｃｔｏｒＬａｓｅｒｗｉｔｈＧｒａｐｈｉｔｅＳｈｅｅｔａｓＡｕｘｉｌｉａｒｙＨｅａｔＳｉｎｋＦＡＮＧＪｕｎ￣ｙｕꎬＳＨＩＬｉｎ￣ｌｉｎ∗ꎬＺＨＡＮＧＨｅꎬＹＡＮＧＺｈｉ￣ｋｕｎꎬＸＵＹｉｎｇ￣ｔｉａｎꎬＸＵＬｉꎬＭＡＸｉａｏ￣ｈｕｉ(ＮａｔｉｏｎａｌＫｅｙＬａｂｏｒａｔｏｒｙｏｎＨｉｇｈＰｏｗｅｒＳｅｍｉｃｏｎｄｕｃｔｏｒＬａｓｅｒꎬＣｈａｎｇｃｈｕｎＵｎｉｖｅｒｓｉｔｙｏｆＳｃｉｅｎｃｅａｎｄＴｅｃｈｎｏｌｏｇｙꎬＣｈａｎｇｃｈｕｎ１３００２２ꎬＣｈｉｎａ)∗ＣｏｒｒｅｓｐｏｎｄｉｎｇＡｕｔｈｏｒꎬＥ￣ｍａｉｌ:ｌｉｎｌｉｎｓｈｉ８８＠ｆｏｘｍａｉｌ.ｃｏｍＡｂｓｔｒａｃｔ:Ｉｎｏｒｄｅｒｔｏｒｅｄｕｃｅｔｈｅｔｅｍｐｅｒａｔｕｒｅｏｆｔｈｅａｃｔｉｖｅｒｅｇｉｏｎｏｆｔｈｅｈｉｇｈ￣ｐｏｗｅｒｓｉｎｇｌｅ￣ｔｕｂｅｓｅｍｉ￣ｃｏｎｄｕｃｔｏｒｌａｓｅｒꎬｉｎｃｒｅａｓｅｔｈｅｈｅａｔｄｉｓｓｉｐａｔｉｏｎｐｅｒｆｏｒｍａｎｃｅｏｆｔｈｅｐａｃｋａｇｅｓｔｒｕｃｔｕｒｅꎬａｎｄｒｅｄｕｃｅｔｈｅｃｏｓｔｏｆｔｈｅｄｅｖｉｃｅｐａｃｋａｇｅꎬａｈｉｇｈ￣ｐｏｗｅｒｓｅｍｉｃｏｎｄｕｃｔｏｒｌａｓｅｒｐａｃｋａｇｅｓｔｒｕｃｔｕｒｅｕｓｉｎｇａｈｉｇｈｔｈｅｒｍａｌｃｏｎｄｕｃｔｉｖｉｔｙｇｒａｐｈｉｔｅｓｈｅｅｔａｓａｎａｕｘｉｌｉａｒｙｈｅａｔｓｉｎｋｉｓｐｒｏｐｏｓｅｄ.Ｕｓｉｎｇｆｉｎｉｔｅｅｌｅｍｅｎｔａｎａｌｙｓｉｓꎬｔｈｅｕｓｅｏｆｇｒａｐｈｉｔｅｓｈｅｅｔｓａｓａｕｘｉｌｉａｒｙｈｅａｔｓｉｎｋｓｈａｓｂｅｅｎｓｔｕｄｉｅｄꎬａｎｄｔｈｅｐａｃｋａｇｅｄｄｅｖｉｃｅｓｈａｖｅｌｏｗｅｒｔｈｅｒｍａｌｒｅｓｉｓｔａｎｃｅａｎｄｂｅｔｔｅｒｈｅａｔｄｉｓｓｉｐａｔｉｏｎ.Ｔｈｅｅｆｆｅｃｔｏｆｔｈｅｖａｒｉａｔｉｏｎｏｆｔｈｅｗｉｄｔｈｄｉｍｅｎｓｉｏｎｏｆｔｈｅｔｒａｎｓｉｔｉｏｎｈｅａｔｓｉｎｋｃｏｐｐｅｒ￣ｔｕｎｇｓｔｅｎａｌｌｏｙａｎｄｔｈｅａｕｘｉｌｉａｒｙｈｅａｔｓｉｎｋｇｒａｐｈｉｔｅｏｎｔｈｅａｃｔｉｖｅｒｅｇｉｏｎｔｅｍｐｅｒａｔｕｒｅｏｆｔｈｅｓｅｍｉｃｏｎｄｕｃｔｏｒｌａｓｅｒｗａｓｉｎｖｅｓｔｉｇａｔｅｄ.Ｃｏｍｐａｒｅｄｗｉｔｈｔｈｅｔｒａｄｉｔｉｏｎａｌｓｔｒｕｃｔｕｒｅｕｓｉｎｇｃｏｐｐｅｒ￣ｔｕｎｇｓｔｅｎａｌｌｏｙａｓｔｈｅｔｒａｎｓｉｔｉｏｎｈｅａｔｓｉｎｋꎬｔｈｅｎｅｗｐａｃｋａｇｅｓｔｒｕｃｔｕｒｅｈａｓａｊｕｎｃｔｉｏｎｔｅｍｐｅｒａｔｕｒｅｏｆ４.５Ｋａｎｄａｔｈｅｒｍａｌｒｅｓｉｓｔａｎｃｅｏｆ０.４５Ｋ/Ｗ.Ａｃｃｏｒｄｉｎｇｔｏｔｈｅｃａｌｃｕｌａｔｉｏｎꎬｔｈｅｍａｘ￣ｉｍｕｍｏｕｔｐｕｔｐｏｗｅｒｏｆｔｈｅｌａｓｅｒｉｓ２０.６Ｗ.Ｕｎｄｅｒｔｈｅｇｕｉｄａｎｃｅｏｆｔｈｅｒｅｓｅａｒｃｈｒｅｓｕｌｔｓꎬｔｈｅｓｔｒｕｃｔｕｒａｌｄｉｍｅｎｓｉｏｎｓｏｆｃｏｐｐｅｒ￣ｔｕｎｇｓｔｅｎａｌｌｏｙａｎｄｇｒａｐｈｉｔｅｃａｎｂｅｄｅｔｅｒｍｉｎｅｄｔｏａｃｈｉｅｖｅｔｈｅｂｅｓｔｈｅａｔｄｉｓｓｉｐａ￣ｔｉｏｎｅｆｆｅｃｔ.Ｋｅｙｗｏｒｄｓ:ｈｉｇｈｐｏｗｄｅｒｓｅｍｉｃｏｎｄｕｃｔｏｒｌａｓｅｒꎻｈｅａｔｄｉｓｓｉｐａｔｉｏｎꎻｇｒａｐｈｉｔｅｈｅａｔｓｉｎｋꎻｆｉｎｉｔｅｅｌｅｍｅｎｔａｎａｌｙｓｉｓꎻｐａｃｋａｇｅｓｔｒｕｃｔｕｒｅ㊀㊀收稿日期:２０１８￣０９￣１８ꎻ修订日期:２０１８￣１２￣０３㊀㊀基金项目:国家自然科学基金(６１８０４０１３)ꎻ吉林省优秀青年科学基金(２０１８０５２０１９４ＪＨ)资助项目ＳｕｐｐｏｒｔｅｄｂｙＮａｔｉｏｎａｌＮａｔｕｒａｌＳｃｉｅｎｃｅＦｏｕｎｄａｔｉｏｎｏｆＣｈｉｎａ(６１８０４０１３)ꎻＥｘｃｅｌｌｅｎｔＹｏｕｔｈＦｏｕｎｄａｔｉｏｎｏｆＪｉｌｉｎＰｒｏｖｉｎｃｅ(２０１８０５２０１９４ＪＨ)９０８㊀发㊀㊀光㊀㊀学㊀㊀报第４０卷１㊀引㊀㊀言半导体激光器具有体积小㊁重量轻㊁光电转换效率高㊁可靠性高等优点ꎬ在医学㊁军事㊁工业等领域有着广泛的应用[１￣３]ꎮ随着科学技术的发展ꎬ人们对半导体激光器的输出功率需求越来越高ꎮ激光器工作时有源区温度升高ꎬ造成激光器波长红移ꎬ阈值电流增大ꎬ光电转换效率下降ꎬ寿命降低等ꎬ严重时会使激光器彻底损坏[４￣５]ꎮ因此ꎬ热管理技术是高功率半导体激光器发展的一个重要环节ꎮ通过研究高功率半导体激光器热传导特性来提高其热管理技术㊁增加封装结构散热性㊁提高半导体激光器的输出功率具有重要意义ꎮ提高器件散热途径的方法主要有两种:一是采用散热性能更好的散热结构ꎻ二是研发出热导率更高的散热材料ꎮ为使高热导率的材料能与管芯热膨胀系数相匹配ꎬ通常使用与激光器芯片热膨胀系数相差较小的过渡热沉来提高材料间的匹配度ꎬ以减小硬焊料对芯片产生的残余应力ꎬ提高器件的可靠性[６]ꎮ常见过渡热沉有氮化铝㊁碳化硅等陶瓷材料和钨铜合金㊁铜钼合金等金属合金材料[７￣１１]ꎮ目前ꎬ国内外所研究的导热性能良好的过渡热沉材料普遍价格昂贵ꎬ且不能突破兼顾热膨胀系数匹配和热导率较高这一瓶颈ꎬ因而在过渡热沉材料的选择与设计方面还有很大的提升空间ꎬ因此需要对热沉材料与结构进行优化设计ꎮ近年来ꎬ石墨因具有优异的机械㊁光学㊁电子和热性能引起了国内外科研工作者的极大关注ꎮ石墨作为一种超高导热材料ꎬ体积小㊁重量轻ꎬ是电子和光子器件热管理的理想材料ꎬ目前在电子器件中已经有了广泛的应用ꎮＯｎｏ等提出使用石墨片作为一种被动部署的散热器ꎬ该散热器可以通过根据温度改变其散热面来控制散热量ꎬ被用作小型卫星上的新型热控装置[１２]ꎮＷｅｎ等使用商业石墨片用作燃料电池的散热器ꎬ石墨片切割成流通形状与通道板结合使热量通过石墨片向外传导ꎬ有效降低燃料电池的反应区域的温度[１３]ꎮ研究表明石墨具有超高导热性ꎬ最高可达１０００Ｗ/(ｍ Ｋ)ꎬ比一般金属导热材料高约３倍ꎬ但是由于石墨导热率的各向异性特征ꎬ横向热传导率较高而纵向热传导率较低以及石墨的热膨胀系数与半导体激光器材料ＧａＡｓ不匹配等难题ꎬ使得石墨在半导体激光器封装结构的应用方面很少有人研究[１４]ꎮ因此ꎬ如何将这种超高热导率石墨应用在半导体激光器封装结构中具有较高的研究价值ꎬ利用其较高的横向导热性ꎬ增大水平方向热通量传导效率ꎬ从而达到减少半导体激光器有源区温度㊁增大半导体激光器输出功率的目的ꎬ成为本文的研究重点[１５]ꎮ本文在传统封装结构的基础上ꎬ通过在过渡热沉两侧引入石墨片作为该结构的辅助热沉ꎬ依据Ｃ￣Ｍｏｕｎｔ封装方式热传导路径ꎬ充分利用石墨极高的横向热导率以达到更好的降低结温的目的ꎮ同时石墨片通过过渡热沉铜钨合金传导芯片所产生的热量ꎬ解决了石墨片与半导体激光器热膨胀系数不匹配的问题ꎮ利用有限元分析软件ＡＮＳＹＳ建立模型ꎬ选用热导率较高的导电材料铜钨合金(ＷＣｕ)作为过渡热沉ꎮ通过模拟结果可以发现ꎬ在减少过渡热沉ＷＣｕ长度和宽度尺寸的情况下ꎬ可以更好地减少封装结构的热阻ꎬ降低半导体激光器结温ꎬ达到了降低器件热阻的目的ꎬ从而提高半导体激光器的输出功率ꎮ２㊀建立模型对传统边发射单管半导体激光器封装结构建立模型ꎬ其中在理论模拟过程中做出如下设定[１６￣１８]:在半导体激光器正常工作过程中ꎬ所产生的热量主要来源于有源区中载流子复合㊁吸收和自发发射ꎻ由于半导体激光器体积较小ꎬ因此忽略激光器的辐射散热及与空气对流散热ꎻ由于Ｃ￣Ｍｏｕｎｔ封装结构的后表面固定在其他制冷结构上ꎬ所以模拟过程中ꎬ在其结构的后平面设置固定温度２９８Ｋꎬ并且半导体激光器芯片采用倒装式封装ꎮ该Ｃ￣Ｍｏｕｎｔ铜热沉尺寸为６.８６ｍｍˑ６.３５ｍｍˑ２.１８ｍｍꎬ由于该半导体激光器封装方式采用Ｃ￣Ｍｏｕｎｔ封装ꎬ其导热路径如图１所示[１９]ꎮCoolerHeatsinkChip图１㊀Ｃ￣Ｍｏｕｎｔ封装导热路径示意图Ｆｉｇ.１㊀ＴｈｅｒｍａｌｃｏｎｄｕｃｔｉｏｎｐａｔｈｉｎＣ￣Ｍｏｕｎｔｐａｃｋａｇｅ㊀第７期房俊宇ꎬ等:石墨片作辅助热沉的高功率半导体激光器热传导特性９０９㊀模拟计算中所使用的半导体激光器光电参数为:波长８０８ｎｍꎬ电光转换效率５０％ꎬ连续条件下输出功率１０Ｗꎬ激光器芯片尺寸为１.５ｍｍˑ０.５ｍｍˑ０.１５ｍｍꎬ发光区宽度１００μｍꎮＷＣｕ热沉尺寸为３.３５ｍｍˑ２.１８ｍｍˑ０.５ｍｍꎮ为满足与激光器芯片热膨胀系数匹配的要求和此后过渡热沉的尺寸设计要求ꎬ选用与铜热膨胀系数匹配的电导率较好的ＷＣｕ材料作为过渡热沉ꎮ为阻挡焊料向下扩散ꎬ便于引线键合ꎬ在过渡热沉铜钨合金的上下表面分别镀有金属层ꎮ模拟分析所涉及的材料参数如表１所示ꎮ表１㊀材料参数Ｔａｂ.１㊀ＭａｔｅｒｉａｌｐａｒａｍｅｔｅｒｓＭａｔｅｒｉａｌＴｈｅｒｍａｌｃｏｎｄｕｃｔｉｖｉｔｙ/(Ｗ ｍ－１ Ｋ－１)Ｔｈｉｃｋｎｅｓｓ/μｍＣｏｅｆｆｉｃｉｅｎｔｏｆｔｈｅｒｍａｌｅｘｐａｎｓｉｏｎ/(１０－６Ｋ)ＧａＡｓ５５１５０６.４ＭｅｔａｌｌｉｚａｔｉｏｎｌａｙｅｒＣｕ３９８０.３１８Ｔｕｎｇｓｔｅｎｃｏｐｐｅｒ２１００.５ˑ１０３４.５ｇｒａｐｈｉｔｅ１０００㊁３５０.５ˑ１０３２ｃｏｐｐｅｒｈｅａｔｓｉｎｋ３９８６.８６ˑ１０３１８在半导体激光器工作过程中ꎬ所产生的热量主要来自以下方面[２０￣２１]:(１)激光器有源区在正常工作状态下有很高的载流子密度和光子密度ꎬ部分电子与空穴非辐射复合㊁辐射吸收与自发辐射吸收ꎬ其产生的热量Ｑ１为:Ｑ１＝Ｖｄａｃｔ{ｊｔｈ(１－ηｓｐｆｓｐ)＋(ｊ－ｊｔｈ)ˑ[１－ηｅｘ－(１－ηｉ)ｆｓｐηｓｐ]}ꎬ(１)其中ꎬＶ为ＰＮ结上的结电压ꎬηｓｐ为自发辐射内量子效率ꎬｆｓｐ为自发辐射光子逃逸因子ꎬｄａｃｔ为有源区厚度ꎬｊ为电流密度ꎬｊｔｈ为阈值电流密度ꎬηｅｘ为外微分量子效率ꎬηｉ为受激辐射内量子效率ꎮ(２)当半导体激光器工作时ꎬ由于各层材料电阻引起的焦耳热ꎬ计算公式为:Ｑ２＝ｊ２ρ＋ρｊ２ｄｃꎬ(２)其中ꎬＱ２为焦耳热功率密度ꎬρ为各材料层的电阻率ꎬｄｃ为欧姆接触层厚度ꎮ(３)盖层以及衬底材料对有源区自发辐射逃逸光子的吸收所产生的热量为:Ｑ３＝Ｖ２ｄｉｊｔｈηｓｐｆꎬ(３)其中ꎬｄｉ为除有源区外各层材料的厚度ꎮ激光器在正常工作状态下ꎬ热传导方程为:Ｋ∂２Ｔ∂ｘ２＋∂２Ｔ∂ｙ２＋∂２Ｔ∂ｚ２()＋Ｑ＝０ꎬ(４)其中ꎬＴ为激光器有源区温度ꎬＫ为材料热传导系数ꎬＱ为半导体激光器热功率密度ꎮ３㊀模拟结果与分析３.１㊀ＷＣｕ热沉宽度的变化对芯片结温的影响金属铜与芯片材料ＧａＡｓ的热膨胀系数差距较大ꎬ为减少封装过程中所带来的封装应力ꎬ采用与ＧａＡｓ的热膨胀系数相近的ＷＣｕ材料作为过渡热沉ꎬ同时由于ＷＣｕ材料具有很好的导电性ꎬ便于正电极连接ꎮ利用有限元分析法探讨在传统封装结构中ꎬＷＣｕ热沉宽度的变化对芯片结温的影响ꎬＷＣｕ热沉的长度与厚度分别为２.１８ｍｍ和０.５ｍｍꎬＷＣｕ宽度由３.３５ｍｍ减少到０.６ｍｍ时ꎬ半导体激光器有源区温度变化如图２所示ꎮ半导体激光器有源区温度为Ｔｊꎬ热沉的最低温度为Ｔ０ꎬ热功率为Ｐｔｅｍꎬ根据激光器热阻Ｒｔｈ的表达式:３５４Ｗ/mmＴ/Ｋ0.5 3.535035２3４８3４６3４４3４２3４０3３８１．０１.5２．０２．53．０T图２㊀半导体激光器有源区温度与铜钨合金宽度Ｗ变化曲线Ｆｉｇ.２㊀Ｖａｒｉａｔｉｏｎｃｕｒｖｅｏｆａｃｔｉｖｅｒｅｇｉｏｎｔｅｍｐｅｒａｔｕｒｅａｎｄｔｕｎｇ￣ｓｔｅｎｃｏｐｐｅｒ(ＣｕＷ)ｗｉｄｔｈＷｖａｌｕｅｏｆｓｅｍｉｃｏｎｄｕｃｔｏｒｌａｓｅｒ㊀９１０㊀发㊀㊀光㊀㊀学㊀㊀报第４０卷Ｒｔｈ＝Ｔｊ－Ｔ０Ｐｔｅｍꎬ(５)从图２中可以看出ꎬ当ＷＣｕ热沉宽度尺寸从３.３５ｍｍ减少到０.６ｍｍ时ꎬ结温从３３９.４Ｋ增加为３５２.２Ｋꎬ热阻从４.１４Ｋ/Ｗ增加到５.４２Ｋ/Ｗꎮ其原因是热沉宽度的减小影响了热流的横向散热ꎬ降低了器件散热能力ꎮ因此ꎬ提高半导体激光器的横向导热性能是改善激光器散热能力的重要瓶颈ꎮ３.２㊀石墨片作辅助热沉热模拟３.２.１㊀石墨片导热性能在固体材料中ꎬ热传导方式主要分为两种ꎮ一种是通过自由电子振动实现ꎬ如金属材料ꎮ另一种由晶体内晶格原子的振动波即声子振动实现ꎬ如石墨[２２]ꎮ在石墨的网状结构中ꎬ声子振动的热振幅很大ꎬ致使石墨具有高的晶面导热系数ꎬ可达１０００Ｗ/(ｍ Ｋ)以上[２３]ꎻ但在垂直网状结构的方向ꎬ由于声子振动的热振幅很小ꎬ在该方向的热导率仅有３５Ｗ/(ｍ Ｋ)ꎮ因此ꎬ石墨片是一种各向导热异性的导热材料ꎬ横向导热率明显优于纵向导热率ꎬ且明显高于常用的金属热沉热导率ꎬ所以在封装领域中有着极高的研究价值ꎮ３.２.２㊀新型封装结构使用石墨片作辅助热沉的新型封装结构示意图如图３所示ꎮ在传统封装结构中ꎬＷＣｕ热沉两边分别使用石墨作为辅助热沉ꎬ石墨首先通过化学镀铜法或电镀铜法使石墨表面金属化ꎬ使石墨表面具有金属的性质ꎬ从而实现石墨分别与铜热沉㊁ＷＣｕ过渡热沉接触面的焊接工艺[２４￣２６]ꎮ表面金属化后的石墨与ＷＣｕ接触部分使用焊料焊接ꎬ使得二者在工作过程中紧密接触ꎮ石墨长度和厚度分别为２.１８ｍｍ和０.５ｍｍꎬ在石墨辅助热沉㊁ＷＣｕ热沉以及Ｃ￣Ｍｏｕｎｔ铜热沉的后表面设置固定温度为２９８Ｋꎮ图３(ｂ)所示为由芯片所产生的热量通过过渡热沉分别向后表面冷却面㊁铜热沉以及石墨片辅助热沉传导散热ꎬ使半导体激光器有源区的温度降低ꎮ铜石墨芯片铜钨合金（a）（b）图３㊀(ａ)石墨片作辅助热沉的新型封装结构示意图ꎻ(ｂ)石墨局部热传递示意图ꎮＦｉｇ.３㊀(ａ)Ｓｃｈｅｍａｔｉｃｄｉａｇｒａｍｏｆｎｅｗｐａｃｋａｇｉｎｇｓｔｒｕｃｔｕｒｅｏｆｇｒａｐｈｉｔｅｓｈｅｅｔａｓａｕｘｉｌｉａｒｙｈｅａｔｓｉｎｋ.(ｂ)Ｓｃｈｅｍａｔｉｃｄｉａｇｒａｍｏｆｌｏ￣ｃａｌｈｅａｔｔｒａｎｓｆｅｒｉｎｇｒａｐｈｉｔｅ.增加石墨片平行于半导体激光器芯片端面方向的尺寸ꎬ同时减少铜钨合金的宽度(Ｗ)ꎬ保证二者宽度尺寸总和为３.３５ｍｍꎮ当ＷＣｕ尺寸分别由２.０ｍｍ变化到０.６ｍｍ时ꎬ计算各个参数下的芯片结温ꎮ如图４所示ꎬ通过不同尺寸下的激光器温度分布云图可以看出ꎬＷＣｕ宽度从２.０ｍｍ减小到０.６ｍｍ时ꎬ结温逐渐下降ꎬ分别从３３８.９Ｋ减小到３３４.９Ｋꎬ热阻Ｒｔｈ也逐渐降低ꎬ从４.０９Ｋ/Ｗ变化为３.６９Ｋ/Ｗꎮ随着ＷＣｕ尺寸的减小ꎬ更多热量传导到石墨片上ꎬ散热效果明显提高ꎬ当铜钨合金热沉的宽度为０.６ｍｍ时ꎬ半导体激光器有源区温度达到最小ꎮ为进一步分析横向热传导性能ꎬ对传统封装结构和石墨片作辅助热沉的封装结构的端面方向热流矢量进行模拟分析ꎬ如图５所示ꎮ其中图５(ａ)㊁(ｂ)分别为Ｗ＝０.６ｍｍ和Ｗ＝３.３５ｍｍ的传统封装结构ꎬ图５(ｃ)㊁(ｄ)分别为Ｗ＝０.６ｍｍ和Ｗ＝２.０ｍｍ的石墨片作辅助热沉的封装结构的热流矢量图ꎮ从图５(ａ)㊁(ｂ)中可以看出ꎬ传统封装结构有源区热量仅向下通过过渡热沉ＷＣｕ和铜热沉进行散热ꎬ当ＷＣｕ热沉尺寸增大(图５(ｂ))ꎬ封装结构热阻与结温温度有所降低ꎮ图５(ｃ)㊁(ｄ)为采用石墨片作辅助热沉的封装结构的热流矢量图ꎬ从图中可以看出ꎬ有源区热量首先扩散到ＷＣｕ热沉中ꎬ由于石墨片具有较高的横向热导率ꎬ致使扩散到ＷＣｕ的热量首先通过石墨㊀第７期房俊宇ꎬ等:石墨片作辅助热沉的高功率半导体激光器热传导特性９１１㊀0.8mm 1.0mm （a ）298307.0302.5311.6316.1325.2320.7329.8334.3338.92.0mm（b ）298324.8315.8306.9302.4311.4320.3329.3338.2333.71.5mm（c ）298311.11.2mm319.9328.7337.5333.1324.3315.5306.7302.3（d ）298（e ）（f ）298330.8314.4336.9328.2332.6323.9319.6315.3310.9306.6302.3336.0327.5331.8323.3319.1314.9310.6306.4298302.2322.6326.7318.5310.3306.2302.10.6mm334.9图４㊀不同过渡热沉宽度尺寸器件温度分布云图Ｆｉｇ.４㊀Ｇｒａｐｈｉｔｅｔｅｍｐｅｒａｔｕｒｅｄｉｓｔｒｉｂｕｔｉｏｎｏｆａｎｅｗｐａｃｋａｇｅｓｔｒｕｃｔｕｒｅｗｉｔｈｄｉｆｆｅｒｅｎｔｗｉｄｔｈｓｏｆｔｕｎｇｓｔｅｎｃａｒｂｉｄｅ（a ）（c ）0.6mm0.6mm（b ）（d ）3.35mm2.0mm图５㊀传统封装结构和石墨片作辅助热沉的封装结构热流矢量图ꎮ(ａ㊁ｂ)传统封装结构热流矢量图ꎻ(ｃ㊁ｄ)石墨片作辅助热沉的封状结构结构热流矢量图ꎬ热量随石墨片尺寸增加ꎬ散热效果明显ꎮＦｉｇ.５㊀Ｔｒａｄｉｔｉｏｎａｌｐａｃｋａｇｅｓｔｒｕｃｔｕｒｅａｎｄｇｒａｐｈｉｔｅｓｈｅｅｔａｓａｕｘｉｌｉａｒｙｈｅａｔｓｉｎｋｐａｃｋａｇｅｓｔｒｕｃｔｕｒｅｈｅａｔｆｌｏｗｖｅｃｔｏｒ.(ａꎬｂ)Ｔｒａｄｉ￣ｔｉｏｎａｌｐａｃｋａｇｅｓｔｒｕｃｔｕｒｅｈｅａｔｆｌｏｗｖｅｃｔｏｒｄｉａｇｒａｍ.(ｃꎬｄ)Ｇｒａｐｈｉｔｅｓｈｅｅｔａｓａｕｘｉｌｉａｒｙｈｅａｔｓｉｎｋｓｅａｌｓｔｒｕｃｔｕｒｅｈｅａｔｆｌｏｗｖｅｃｔｏｒ.Ｔｈｅｈｅａｔｉｓｏｂｖｉｏｕｓｌｙｉｎｃｒｅａｓｅｄｗｉｔｈｔｈｅｓｉｚｅｏｆｔｈｅｇｒａｐｈｉｔｅｓｈｅｅｔ.片进行散热ꎬ其次再通过ＷＣｕ和铜散热ꎬ随着石墨片尺寸的增大散热效果明显ꎮ因此ꎬ相比传统封装结构ꎬ通过对石墨辅助热沉的引入ꎬ利用其极高的热导率增大了封装结构的散热途径ꎬ可以很好地减小封装结构的热阻Ｒｔｈ和半导体激光器有源区温度Ｔｊꎬ进而可以很好地降低连续工作的半导体激光器所产生的热量ꎮ对于半导体激光器ꎬ其结温计算表达式为:Ｔｊ＝Ｔ０＋(Ｐｉｎ－Ｐ)Ｒｔｈꎬ(６)其中ꎬＴｊ为激光器芯片结温ꎬＴ０为热沉温度ꎬＰｉｎ为激光器的输入功率ꎬＰ为激光器的输出功率ꎬＲｔｈ为热阻ꎮ由上述公式可知ꎬ激光器芯片结温受工作电流㊁热沉温度及器件热阻影响ꎮ半导体激光器阈值电流和有源区温度之间的关系为:Ｉｔｈ(Ｔ)＝ＩＲｅｔｅｘｐＴ－ＴＲｅｔＴｔæèçöø÷ꎬ(７)其中ꎬＩＲｅｔ为温度ＴＲｅｔ下的阈值电流ꎬＴｔ为激光器特征温度ꎬ主要由激光器结构和材料决定ꎮ激光器斜率效率η随有源区温度变化的表达式为:η(Ｔ)＝η(Ｔｒ)ｅｘｐ－(Ｔ－Ｔｒ)Ｔ１[]ꎬ(８)式中Ｔ１为斜率效率的特征温度ꎮ激光器输出功率与斜率效率和工作电流的关系为:Ｐ＝η(Ｔ)Ｉꎬ(９)结合公式(６)㊁(７)㊁(８)㊁(９)可得出输出功率Ｐ:Ｐ＝ηｅｘｐ－Ｒｔｈ(ＩＶ－Ｐ)Ｔ１[]Ｉ－ＩＲｅｔｅｘｐＲｔｈ(ＩＶ－Ｐ)Ｔ０[]{}.(１０)９１２㊀发㊀㊀光㊀㊀学㊀㊀报第４０卷20535I /AP /W20.6W 18.8WR th =4.14R th =3.691015202530151050图６㊀不同热阻下的Ｐ￣Ｉ特性曲线Ｆｉｇ.６㊀ＣｈａｒａｃｔｅｒｉｓｔｉｃｃｕｒｖｅｏｆＰ￣Ｉｕｎｄｅｒｄｉｆｆｅｒｅｎｔｔｈｅｒｍａｌｒｅ￣ｓｉｓｔａｎｃｅ半导体激光器的输出功率与输入电流的关系曲线如图６所示ꎮ从图中可以看出随着封装热阻的减少ꎬ器件输出功率会增加ꎮ经过本文封装结构优化后ꎬ封装热阻降为３.６９Ｋ/Ｗꎬ其最大输出功率为２０.６Ｗꎮ４㊀结㊀㊀论为了降低边缘式高功率半导体激光器有源区温度ꎬ降低器件封装成本ꎬ在Ｃ￣Ｍｏｕｎｔ封装结构的基础上ꎬ研究了一种使用石墨材料作为辅助热沉的封装结构ꎬ并理论分析比较其输出功率与传统封装结构的输出功率ꎮ在传统封装结构中ꎬ过渡热沉ＷＣｕ宽度尺寸从３.３５ｍｍ减小到０.６ｍｍ时ꎬ半导体激光器有源区温度从３３９.４Ｋ升高到３５２.２Ｋꎮ在使用石墨作辅助热沉的条件下ꎬ石墨片与ＷＣｕ宽度和为３.３５ｍｍꎬ当过渡热沉尺寸从２.０ｍｍ减少到０.６ｍｍ时ꎬ结温从３３８.９Ｋ降到３３４.９Ｋꎮ相比于宽为３.３５ｍｍ的ＷＣｕ传统结构ꎬ其温度降低４.５Ｋꎮ在传统封装结构中ꎬ随着ＷＣｕ宽度的减少ꎬ有源区温度升高ꎮ而新型封装结构与其相反ꎬ相比于传统结构ꎬ有源区温度降低４.５Ｋꎬ散热效果明显改善ꎮ通过计算可知ꎬ半导体激光器的最大输出功率为２０.６Ｗꎮ该结构设计为今后高功率半导体激光器的发展提供了帮助ꎬ同时在商业上有着很高的使用价值ꎮ参㊀考㊀文㊀献:[１]韩晓俊ꎬ李正佳ꎬ朱长虹.半导体激光器在医学上的应用[Ｊ].光学技术ꎬ１９９８(２):７￣１０.ＨＡＮＸＪꎬＬＩＺＪꎬＺＨＵＣＨ.Ｌａｓｅｒｄｉｏｄｅａｐｐｌｉｅｄｉｎｍｅｄｉｃｉｎｅ[Ｊ].Ｏｐｔ.Ｔｅｃｈｎｏｌ.ꎬ１９９８(２):７￣１０.(ｉｎＣｈｉｎｅｓｅ)[２]耿素杰ꎬ王琳.半导体激光器及其在军事领域的应用[Ｊ].激光与红外ꎬ２００３ꎬ３３(４):３１１￣３１２.ＧＥＮＧＳＪꎬＷＡＮＧＬ.Ｔｈｅｓｅｍｉｃｏｎｄｕｃｔｏｒｌａｓｅｒａｎｄｉｔｓａｐｐｌｉｃａｔｉｏｎｓｉｎｍｉｌｉｔａｒｙ[Ｊ].ＬａｓｅｒＩｎｆｒａｒｅｄꎬ２００３ꎬ３３(４):３１１￣３１２.(ｉｎＣｈｉｎｅｓｅ)[３]张纯.半导体激光器在印刷工业上的应用[Ｊ].光电子 激光ꎬ１９９１ꎬ２(４):２３１￣２３５.ＺＨＡＮＧＣ.Ｔｈｅａｐｐｌｉｃａｔｉｏｎｏｆｔｈｅｔｒａｎｓｉｓｔｏｒ￣ｌａｓｅｒｉｎｔｈｅｐｒｉｎｔｉｎｇｉｎｄｕｓｔｒｙ[Ｊ].Ｊ.Ｏｐｔｏｅｌｅｃｔｒ.Ｌａｓｅｒꎬ１９９１ꎬ２(４):２３１￣２３５.(ｉｎＣｈｉｎｅｓｅ)[４]汪瑜.半导体激光器热特性分析研究[Ｄ].长春:长春理工大学ꎬ２００９:１６￣１７.ＷＡＮＧＹ.ＡｎａｌｙｓｉｓａｎｄＲｅｓｅａｒｃｈｆｏｒＴｈｅＴｈｅｒｍａｌＣｈａｒａｃｔｅｒｉｓｔｉｃｏｆＴｈｅＳｅｍｉｃｏｎｄｕｃｔｏｒＬａｓｅｒ[Ｄ].Ｃｈａｎｇｃｈｕｎ:ＣｈａｎｇｃｈｕｎＵｎｉｖｅｒｓｉｔｙｏｆＳｃｉｅｎｃｅａｎｄＴｅｃｈｎｏｌｏｇｙꎬ２００９:１６￣１７.(ｉｎＣｈｉｎｅｓｅ)[５]廖翌如ꎬ关宝璐ꎬ李建军ꎬ等.低阈值８５２ｎｍ半导体激光器的温度特性[Ｊ].发光学报ꎬ２０１７ꎬ３８(３):３３１￣３３７.ＬＩＡＯＹＲꎬＧＵＡＮＢＬꎬＬＩＪＪꎬｅｔａｌ..Ｔｈｅｒｍａｌｃｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｔｈｅｌｏｗｔｈｒｅｓｈｏｌｄ８５２ｎｍｓｅｍｉｃｏｎｄｕｃｔｏｒｌａｓｅｒｓ[Ｊ].Ｃｈｉｎ.Ｊ.Ｌｕｍｉｎ.ꎬ２０１７ꎬ３８(３):３３１￣３３７.(ｉｎＣｈｉｎｅｓｅ)[６]王辉.半导体激光器封装中热应力和变形的分析[Ｊ].半导体技术ꎬ２００８ꎬ３３(８):７１８￣７２０.ＷＡＮＧＨ.Ｔｈｅｒｍａｌｓｔｒｅｓｓａｎｄｄｅｆｏｒｍａｔｉｏｎａｎａｌｙｓｉｓｏｆｓｅｍｉｃｏｎｄｕｃｔｏｒｌａｓｅｒｓｐａｃｋａｇｉｎｇ[Ｊ].Ｓｅｍｉｃｏｎｄ.Ｔｅｃｈｎｏｌ.ꎬ２００８ꎬ３３(８):７１８￣７２０.(ｉｎＣｈｉｎｅｓｅ)[７]ＺＨＡＮＧＸＬꎬＢＯＢＸꎬＱＩＡＯＺＬꎬｅｔａｌ..Ａｎａｌｙｓｉｓｏｆｔｈｅｒｍａｌｃｈａｒａｃｔｅｒｉｓｔｉｃｓｂａｓｅｄｏｎａｎｅｗｔｙｐｅｄｉｏｄｅｌａｓｅｒｐａｃｋａｇｉｎｇｓｔｒｕｃｔｕｒｅ[Ｊ].Ｏｐｔ.Ｅｎｇ.ꎬ２０１７ꎬ５６(８):０８５１０５￣１￣５.[８]刘一兵ꎬ戴瑜兴ꎬ黄志刚.照明用大功率发光二极管封装材料的优化设计[Ｊ].光子学报ꎬ２０１１ꎬ４０(５):６６３￣６６６.ＬＩＵＹＢꎬＤＡＩＹＸꎬＨＵＡＮＧＺＧ.Ｏｐｔｉｍｉｚａｔｉｏｎｄｅｓｉｇｎｏｎｐａｃｋａｇｉｎｇｍａｔｅｒｉａｌｓｏｆｈｉｇｈ￣ｐｏｗｅｒＬＥＤｆｏｒｌｉｇｈｔｉｎｇ[Ｊ].ＡｃｔａＰｈｏｔｏｎ.Ｓｉｎｉｃａꎬ２０１１ꎬ４０(５):６６３￣６６６.(ｉｎＣｈｉｎｅｓｅ)[９]倪羽茜ꎬ井红旗ꎬ孔金霞ꎬ等.碳化硅封装高功率半导体激光器散热性能研究[Ｊ].中国激光ꎬ２０１８ꎬ４５(１):㊀第７期房俊宇ꎬ等:石墨片作辅助热沉的高功率半导体激光器热传导特性９１３㊀０１０１００２￣１￣５.ＮＩＹＸꎬＪＩＮＧＨＱꎬＫＯＮＧＪＸꎬｅｔａｌ..Ｔｈｅｒｍａｌｐｅｒｆｏｒｍａｎｃｅｏｆｈｉｇｈ￣ｐｏｗｅｒｌａｓｅｒｄｉｏｄｅｓｐａｃｋａｇｅｄｂｙＳｉＣｃｅｒａｍｉｃｓｕｂｍｏｕｎｔ[Ｊ].Ｃｈｉｎ.Ｊ.Ｌａｓｅｒｓꎬ２０１８ꎬ４５(１):０１０１００２￣１￣５.(ｉｎＣｈｉｎｅｓｅ)[１０]ＫＵＣＭꎬＷＡＳＩＡＫＭꎬＳＡＲＺＡＬＡＲＰ.ＩｍｐａｃｔｏｆｈｅａｔｓｐｒｅａｄｅｒｓｏｎｔｈｅｒｍａｌｐｅｒｆｏｒｍａｎｃｅｏｆⅢ￣Ｎ￣ｂａｓｅｄｌａｓｅｒｄｉｏｄｅ[Ｊ].ＩＥＥＥＴｒａｎｓ.Ｃｏｍｐ.ꎬＰａｃｋ.Ｍａｎｕｆ.Ｔｅｃｈｎｏｌ.ꎬ２０１５ꎬ５(４):４７４￣４８２.[１１]王文ꎬ许留洋ꎬ王云华ꎬ等.热沉尺寸对半导体激光器有源区温度的影响[Ｊ].半导体光电ꎬ２０１３ꎬ３４(５):７６５￣７６９.ＷＡＮＧＷꎬＸＵＬＹꎬＷＡＮＧＹＨꎬｅｔａｌ..Ｉｎｆｌｕｅｎｃｅｓｏｆｔｈｅｄｉｍｅｎｓｉｏｎｏｆｈｅａｔｓｉｎｋｏｎｔｈｅｔｅｍｐｅｒａｔｕｒｅｏｆａｃｔｉｖｅｒｅｇｉｏｎｉｎｓｅｍｉｃｏｎｄｕｃｔｏｒｌａｓｅｒ[Ｊ].Ｓｅｍｉｃｏｎｄ.Ｏｐｔｏｅｌｅｃｔｒ.ꎬ２０１３ꎬ３４(５):７６５￣７６９.(ｉｎＣｈｉｎｅｓｅ)[１２]ＯＮＯＳꎬＮＡＧＡＮＯＨꎬＮＩＳＨＩＫＡＷＡＹꎬｅｔａｌ..Ｔｈｅｒｍｏｐｈｙｓｉｃａｌｐｒｏｐｅｒｔｉｅｓｏｆｈｉｇｈ￣ｔｈｅｒｍａｌ￣ｃｏｎｄｕｃｔｉｖｉｔｙｇｒａｐｈｉｔｅｓｈｅｅｔａｎｄａｐｐｌｉｃａｔｉｏｎｔｏｄｅｐｌｏｙａｂｌｅ/ｓｔｏｗａｂｌｅｒａｄｉａｔｏｒ[Ｊ].Ｊ.Ｔｈｅｒｍｏｐｈｙｓ.ＨｅａｔＴｒａｎｓ.ꎬ２０１５ꎬ２９(２):３４７￣３５３.[１３]ＷＥＮＣＹꎬＨＵＡＮＧＧＷ.ＡｐｐｌｉｃａｔｉｏｎｏｆａｔｈｅｒｍａｌｌｙｃｏｎｄｕｃｔｉｖｅｐｙｒｏｌｙｔｉｃｇｒａｐｈｉｔｅｓｈｅｅｔｔｏｔｈｅｒｍａｌｍａｎａｇｅｍｅｎｔｏｆａＰＥＭｆｕｅｌｃｅｌｌ[Ｊ].Ｊ.ＰｏｗｅｒＳｏｕｒｃｅｓꎬ２００８ꎬ１７８(１):１３２￣１４０.[１４]ＭＡＬＥＫＰＯＵＲＨꎬＣＨＡＮＧＫＨꎬＣＨＥＮＪＣꎬｅｔａｌ..Ｔｈｅｒｍａｌｃｏｎｄｕｃｔｉｖｉｔｙｏｆｇｒａｐｈｅｎｅｌａｍｉｎａｔｅ[Ｊ].ＮａｎｏＬｅｔｔ.ꎬ２０１４ꎬ１４(９):５１５５￣５１６１.[１５]ＷＡＮＧＹＸꎬＯＶＥＲＭＥＹＥＲＬ.Ｃｈｉｐ￣ｌｅｖｅｌｐａｃｋａｇｉｎｇｏｆｅｄｇｅ￣ｅｍｉｔｔｉｎｇｌａｓｅｒｄｉｏｄｅｓｏｎｔｏｌｏｗ￣ｃｏｓｔｔｒａｎｓｐａｒｅｎｔｐｏｌｙｍｅｒｓｕｂ￣ｓｔｒａｔｅｓｕｓｉｎｇｏｐｔｏｄｉｃｂｏｎｄｉｎｇ[Ｊ].ＩＥＥＥＴｒａｎｓ.Ｃｏｍｐ.ꎬＰａｃｋ.Ｍａｎｕｆ.Ｔｅｃｈｎｏｌ.ꎬ２０１６ꎬ６(５):６６７￣６７４.[１６]王文ꎬ高欣ꎬ周泽鹏ꎬ等.百瓦级多芯片半导体激光器稳态热分析[Ｊ].红外与激光工程ꎬ２０１４ꎬ４３(５):１４３８￣１４４３.ＷＡＮＧＷꎬＧＡＯＸꎬＺＨＯＵＺＰꎬｅｔａｌ..Ｓｔｅａｄｙ￣ｓｔａｔｅｔｈｅｒｍａｌａｎａｌｙｓｉｓｏｆｈｕｎｄｒｅｄ￣ｗａｔｔｓｅｍｉｃｏｎｄｕｃｔｏｒｌａｓｅｒｗｉｔｈｍｕｌｔｉｃｈｉｐ￣ｐａｃｋａｇｉｎｇ[Ｊ].ＩｎｆｒａｒｅｄＬａｓｅｒＥｎｇ.ꎬ２０１４ꎬ４３(５):１４３８￣１４４３.(ｉｎＣｈｉｎｅｓｅ)[１７]杨宏宇ꎬ舒世立ꎬ刘林ꎬ等.半导体激光器模块散热特性影响因素分析[Ｊ].半导体光电ꎬ２０１６ꎬ３７(６):７７０￣７７５.ＹＡＮＧＨＹꎬＳＨＵＳＬꎬＬＩＵＬꎬｅｔａｌ..Ａｎａｌｙｓｉｓｏｎｉｎｆｌｕｅｎｃｉｎｇｆａｃｔｏｒｓｏｆｈｅａｔｄｉｓｓｉｐａｔｉｏｎｃｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｓｅｍｉｃｏｎｄｕｃｔｏｒｌａ￣ｓｅｒｍｏｄｕｌｅ[Ｊ].Ｓｅｍｉｃｏｎｄ.Ｏｐｔｏｅｌｅｃｔｒ.ꎬ２０１６ꎬ３７(６):７７０￣７７５.(ｉｎＣｈｉｎｅｓｅ)[１８]韩立ꎬ徐莉ꎬ李洋ꎬ等.基于Ｃ￣ｍｏｕｎｔ封装的半导体激光器热特性模拟分析[Ｊ].长春理工大学学报(自然科学版)ꎬ２０１６ꎬ３９(３):２７￣３１.ＨＡＮＬꎬＸＵＬꎬＬＩＹꎬｅｔａｌ..ＴｈｅｒｍａｌｃｈａｒａｃｔｅｒｉｓｔｉｃｓｉｍｕｌａｔｉｏｎａｎｄａｎａｌｙｓｉｓｏｆｓｅｍｉｃｏｎｄｕｃｔｏｒｌａｓｅｒｂａｓｅｄｏｎＣ￣ｍｏｕｎｔ[Ｊ].Ｊ.ＣｈａｎｇｃｈｕｎＵｎｉｖ.Ｓｃｉ.Ｔｅｃｈｎｏｌ.(Ｎａｔ.Ｓｃｉ.Ｅｄ.)ꎬ２０１６ꎬ３９(３):２７￣３１.(ｉｎＣｈｉｎｅｓｅ)[１９]ＬＩＸＮꎬＺＨＡＮＧＹＸꎬＷＡＮＧＪＷꎬｅｔａｌ..Ｉｎｆｌｕｅｎｃｅｏｆｐａｃｋａｇｅｓｔｒｕｃｔｕｒｅｏｎｔｈｅｐｅｒｆｏｒｍａｎｃｅｏｆｔｈｅｓｉｎｇｌｅｅｍｉｔｔｅｒｄｉｏｄｅｌａ￣ｓｅｒ[Ｊ].ＩＥＥＥＴｒａｎｓ.Ｃｏｍｐ.ꎬＰａｃｋ.Ｍａｎｕｆ.Ｔｅｃｈｎｏｌ.ꎬ２０１２ꎬ２(１０):１５９２￣１５９９.[２０]井红旗ꎬ仲莉ꎬ倪羽茜ꎬ等.高功率密度激光二极管叠层散热结构的热分析[Ｊ].发光学报ꎬ２０１６ꎬ３７(１):８１￣８７.ＪＩＮＧＨＱꎬＺＨＯＮＧＬꎬＮＩＹＸꎬｅｔａｌ..Ｔｈｅｒｍａｌａｎａｌｙｓｉｓｏｆｈｉｇｈｐｏｗｅｒｄｅｎｓｉｔｙｌａｓｅｒｄｉｏｄｅｓｔａｃｋｃｏｏｌｉｎｇｓｔｒｕｃｔｕｒｅ[Ｊ].Ｃｈｉｎ.Ｊ.Ｌｕｍｉｎ.ꎬ２０１６ꎬ３７(１):８１￣８７.(ｉｎＣｈｉｎｅｓｅ)[２１]姜晓光ꎬ赵英杰ꎬ吴志全.基于ＡＮＳＹＳ半导体激光器热特性模拟与分析[Ｊ].长春理工大学学报(自然科学版)ꎬ２０１０ꎬ３３(１):４１￣４３.ＪＩＡＮＧＸＧꎬＺＨＡＯＹＪꎬＷＵＺＱ.ＴｈｅｒｍａｌｃｈａｒａｃｔｅｒｉｓｔｉｃｓｉｍｕｌａｔｉｏｎａｎｄａｎａｌｙｓｉｓｏｆｓｅｍｉｃｏｎｄｕｃｔｏｒｌａｓｅｒｂａｓｅｄｏｎＡＮＳＹＳ[Ｊ].Ｊ.ＣｈａｎｇｃｈｕｎＵｎｉｖ.Ｓｃｉ.Ｔｅｃｈｎｏｌ.(Ｎａｔ.Ｓｃｉ.Ｅｄ.)ꎬ２０１０ꎬ３３(１):４１￣４３.(ｉｎＣｈｉｎｅｓｅ)[２２]杨振忠ꎬ马忠良ꎬ王峰.基于石墨导热介质的新型ＬＥＤ路灯散热系统[Ｊ].照明工程学报ꎬ２０１１ꎬ２２(３):４９￣５２.ＹＡＮＧＺＺꎬＭＡＺＬꎬＷＡＮＧＦ.ＡｎｅｗＬＥＤｒｏａｄｌｉｇｈｔｉｎｇｌｕｍｉｎａｉｒｅｈｅａｔｄｉｓｓｉｐａｔｉｏｎｓｙｓｔｅｍｂａｓｅｄｏｎｇｒａｐｈｉｔｅｍａｔｅｒｉａｌ[Ｊ].ＣｈｉｎａＩｌｌｕｍ.Ｅｎｇ.Ｊ.ꎬ２０１１ꎬ２２(３):４９￣５２.(ｉｎＣｈｉｎｅｓｅ)[２３]邱海鹏ꎬ郭全贵ꎬ宋永忠ꎬ等.石墨材料导热性能与微晶参数关系的研究[Ｊ].新型炭材料ꎬ２００２ꎬ１７(１):３６￣４０.ＱＩＵＨＰꎬＧＵＯＱＧꎬＳＯＮＧＹＺꎬｅｔａｌ..Ｓｔｕｄｙｏｆｔｈｅｒｅｌａｔｉｏｎｓｈｉｐｂｅｔｗｅｅｎｔｈｅｒｍａｌｃｏｎｄｕｃｔｉｖｉｔｙａｎｄｍｉｃｒｏｃｒｙｓｔａｌｌｉｎｅｐａｒａｍ￣ｅｔｅｒｓｏｆｂｕｌｋｇｒａｐｈｉｔｅ[Ｊ].ＮｅｗＣａｒｂｏｎＭａｔｅｒ.ꎬ２００２ꎬ１７(１):３６￣４０.(ｉｎＣｈｉｎｅｓｅ)[２４]程小爱ꎬ曹晓燕ꎬ张慧玲ꎬ等.石墨表面金属化处理及检测[Ｊ].表面技术ꎬ２００６ꎬ３５(３):４￣７.ＣＨＥＮＧＸＡꎬＣＡＯＸＹꎬＺＨＡＮＧＨＬꎬｅｔａｌ..Ｍｅｔａｌ￣ｍｏｄｉｆｉｃａｔｉｏｎａｎｄｄｅｔｅｃｔｉｏｎｏｆｇｒａｐｈｉｔｅｓｕｒｆａｃｅ[Ｊ].Ｓｕｒｆ.Ｔｅｃｈｎｏｌ.ꎬ２００６ꎬ３５(３):４￣７.(ｉｎＣｈｉｎｅｓｅ)[２５]黄凯ꎬ白华ꎬ朱英彬ꎬ等.石墨表面化学镀Ｃｕ对天然鳞片石墨/Ａｌ复合材料热物理性能的影响[Ｊ].复合材料学报ꎬ２０１８ꎬ３５(４):９２０￣９２６.９１４㊀发㊀㊀光㊀㊀学㊀㊀报第４０卷ＨＵＡＮＧＫꎬＢＡＩＨꎬＺＨＵＹＢꎬｅｔａｌ..Ｔｈｅｒｍａｌｃｏｎｄｕｃｔｉｖｉｔｙａｎｄｍｅｃｈａｎｉｃａｌｐｒｏｐｅｒｔｉｅｓｏｆｆｌａｋｇｒａｐｈｉｔｅ/ＡｌｃｏｍｐｏｓｉｔｅｗｉｔｈｅｌｅｃｔｒｏｌｅｓｓＣｕｐｌａｔｉｎｇｏｎｇｒａｐｈｉｔｅｓｕｒｆａｃｅ[Ｊ].ＡｃｔａＭａｔｅｒ.Ｃｏｍｐ.Ｓｉｎｉｃａꎬ２０１８ꎬ３５(４):９２０￣９２６.(ｉｎＣｈｉｎｅｓｅ)[２６]ＳＯＮＧＸＧꎬＣＨＡＩＪＨꎬＨＵＳＰꎬｅｔａｌ..Ａｎｏｖｅｌｍｅｔａｌｌｉｚａｔｉｏｎｐｒｏｃｅｓｓｆｏｒｓｏｌｄｅｒｉｎｇｇｒａｐｈｉｔｅｔｏｃｏｐｐｅｒａｔｌｏｗｔｅｍｐｅｒａｔｕｒｅ[Ｊ].Ｊ.Ａｌｌｏｙ.Ｃｏｍｐ.ꎬ２０１６ꎬ６９６:１１９９￣１２０４.房俊宇(１９９４－)ꎬ男ꎬ吉林松原人ꎬ硕士研究生ꎬ２０１７年于长春理工大学光电信息学院获得学士学位ꎬ主要从事半导体激光器的研究ꎮＥ￣ｍａｉｌ:４４２１７６２８７＠ｑｑ.ｃｏｍ石琳琳(１９８８－)ꎬ女ꎬ吉林长春人ꎬ博士ꎬ助理研究员ꎬ２０１６年于中国科学院长春光学精密机械与物理研究所获得博士学位ꎬ主要从事半导体激光器物理与技术的研究ꎮＥ￣ｍａｉｌ:ｌｉｎｌｉｎｓｈｉ８８＠ｆｏｘｍａｉｌ.ｃｏｍ。
有限元法单元英语
有限元法释义finit element method[计] 有限元法;finite element method有限元素法;点击人工翻译，了解更多人工释义实用场景例句全部The finite - element method is the most versatile.有限元法是最有用的方法.辞典例句The rectangular groove guide ( RGG ) is analyzed by finite element method ( FEM ) .本文用有限元法分析了矩形槽波导.互联网According to axi - symmetry of shaft, the semi - analytical finite element method is used.考虑到结构的轴对称性质, 分析时采用了半分析有限元法.互联网FEM FCT is used to solve three dimensional hypersonic inviscid flow.从Euler方程出发,利用流量修正有限元法(FEM?FCT)求解三维无粘流动的高速流场.互联网The result are compared with the finite element method's, and anastomosed. "本文计算结果与有限元法分析结果作了比较, 结果吻合较好.互联网Method: 3 - D finite element modeling was computed and analyzed.方法: 采用三维有限元法建立模型并计算、分析.互联网The cloth draping property is studied by using finite element method.以梁单元为模型,运用有限元法研究织物的悬垂性问题.互联网Therefore, the core question of rigid - viscoplastic finite element method has been solved.从而解决了刚粘塑性有限元法核心问题.互联网A permanent magnetic field for mono - crystal furnace was designed.采用有限元法设计了硅单晶炉用永磁磁体.互联网The edge finite element interpolation function of 1 - forms for prism is derived.就三梭柱单元导出了棱边有限元法的1 -形式线性插值基函数.互联网Methods: Three - dimensional finite element analysiswas adopted.方法: 采用三维有限元法.互联网A mixed method - NES FEM is systematically illustrated.提出了新型等效源法与有限元法的一种新耦合算法.互联网The finite element method was used for analysis of heat stress in chip on board ( COB ).本文采用有限元法分析了板上芯片( COB ) 的热应力分布.互联网Finite element method ( FEM ) occupies an important part in Computer Aided Engineering ( CAE ) methods.有限元法,也称有限单元法或有限元素法,在计算机辅助工程CAE 中占有重要的位置.互联网A finite element model for drawing process of high carbon wire with inner micro - defects was built.通过对高碳盘条内部缺陷的假设,采用有限元法研究了高碳盘条拉拔过程中,工艺参数对裂纹扩展情况的影响.互联网。
Finite Element Analysis（FEA）的应用与优化指南说明书
▪▪▪▪Agenda▪Session Approach▪Finite Element Analysis (FEA) Overview ▪FEA Parameters▪FEA Best Practices▪FEA Software Introduction▪Analysis WalkthroughThis session is not just theoretical information… there’s just not enough time to teach everyone matrix algebraWe are going to apply and leverage modern technology to gain insights into the use cases and capabilitiesFEA DescriptionFinite Element Analysis (FEA) is a computerized method for predicting how a real-world object will react to forces, vibration, heat, etc. to determine whether or not it will function as plannedFEA Benefits▪Predict Product Performance▪Reduce Raw Materials▪Ensure Optimal Design▪Verification▪Reduce Manual Testing and Prototypes ▪Test What If Scenarios▪Shorten Design CycleWho Uses Simulation?The Engineer The AnalystFEA Process Overview1.CAD Model Creation2.Simulation Setup3.Solve Simulation4.Review Results5.OptimizeMeshed 3D Model ExampleElement OverviewAn element is a mathematical relation that defines how the DOFs of one node relate to the next.Node OverviewA node is a coordinate location in space where the Degrees of Freedom (DOFs) are defined.Types of Elements▪1D elements▪ A line connecting 2 nodes only for items like beams and springs▪2D elements▪Planar or axisymmetric elements with either three or four edges enclosing an area▪Plates or Shell Elements: Planar elements that are triangular or quadrilateral with a specifiedthickness▪3D (solid) elements▪Enclosed 3D volumes with 4, 5, 6 or 8 corner nodesStandard Element BondingElements within a single part body can only communicate to one another via common nodes for transferring data information No Connection Connected NodesMaterial Assignment▪Material properties define the structure characteristics of the part ▪Material property information can be located at LoadsStructural loads are forces applied to a part or assembly during operation and cause the model to displace, deflect, and induce stresses and strainsConstraintsStructural constraints restrict or limit the displacement of the model mesh nodesContact ConditionsContact conditions are used to establish relationships between the nodes of contacting parts within an assemblySimulation SolvingRunning or solving the simulation processes and calculates the results based on the parameters establishedResultsThe simulation results can be reviewed and exported as a report to make intelligent decisionsReviewing Results▪Simulation does not always replace the need for physical testing ▪The engineer / analyst still needs to interpret the results to make final decisionsAnalysis Types▪LinearFocus for this presentation ▪Nonlinear▪Thermal / Electrostatic▪Natural Frequency / Modal Analysis▪Vibration▪Fatigue AnalysisLinear vs. Nonlinear▪LinearFocus for this presentation ▪Structure returns to original form▪Small changes in shape stiffness▪No changes in loading direction or magnitude▪Material properties do not change▪Small deformation and strain▪Nonlinear▪Geometry changes resulting in stiffness change▪Material deformation that may not return to original form▪Supports changes in load direction and constraint locations ▪Support of nonlinear load curvesMild Steel Material Properties▪Density = 0.284 lbmass/in^3▪Young’s Modulus = 3.193E+4 ksi▪Poisson’s Ratio = 0.275▪Yield Strength = 3.004E+4 psi▪Ultimate Tensile Strength = 5.007E+4 psi▪Thermal Conductivity = 1.259E+3 btu in/(ft^2 hr*F) ▪Linear Expansion = 21.600E-6 in/(in*F)▪Specific Heat = 0.356 btu/(lbmass*F)Strain Hardening Mild Steel Stress Strain Curve S t r e s s =Strain = Yield Strength (Elastic Limit) Ultimate StrengthFailure NeckingChange in LengthOriginal LengthA r e a F o r c eDisplacementThe displacement results show the magnitude of the model deformation from the original shapeVon Mises StressFormula for combining three principal stresses into an equivalent stress to compare to the material stress propertiesSafety FactorProvides a ratio of how much stronger the object is than it usually needs to be for an intended loadMaterial Yield Strength Safety Factor =Maximum Von Mises Stress40,000 psi2 =20,000 psiConvergenceConvergence is the process of altering element sizes in high stress areas to ensure the specified result criteria has convergedStress SingularitiesA localized high stress area where the stress becomes infinite resulting in distorted resultsBest Practices▪Setup simulation to match real world▪Verify material properties▪Use engineering knowledge judgment▪Avoid putting loads on nodes or small edges ▪Ensure solution type (Linear / Nonlinear)▪Identify stress singularities▪Ensure your results convergeFEA Software▪Conceptual Simulation (Apps)▪FEA Features Built into Design Tools▪Purpose Built Simulation Software Focus for thispresentationAutodesk Simulation Mechanical▪Importing geometry▪Assigning loads and constraints▪Evaluating results▪Results based optimizationRecap▪Finite Element Analysis (FEA) Overview ▪FEA Parameters▪FEA Best Practices▪FEA Software Introduction▪Analysis WalkthroughThank You!Questions?▪Contact: ***********************▪Products: /simulation ▪Community: Session Feedback▪Via the Survey Stations, email or mobile device ▪AU 2015 passes given out each day!▪Best to do it right after the session▪Instructors see results in real-time。
MEMS微系统 复习红宝书(北理)
20.BGA : Ball Grid Array 球状矩阵排列
21.SHM:Structural Health Monitoring 结构健康监测
22.ICT:Information and Communications Technologies 信息与通信技术
23.MtM More than Moore 超越摩尔定律
24.FEA:Finite Element Analysis 有限元分析
25.SEM:Scanning Electron Microscope 扫描电子显微镜
12.ITRS International technology Roadmap for Semiconductor 国际半导体技术规
划
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27.DARPA :Defence Advanced Research Projects Agency of theDepartment of
成，它们各具不同的能带隙。这些材料可以是 GaAs 之类的化合物，也可以是 Si-Ge 之类的半导体合金。按异质结中两种材料导带和价带的对准情况可以把异 质结分为Ⅰ型异质结和Ⅱ型异质结两种。 12.微加工：以微小切除量获得很高精度的尺寸和形状的加工。 13.引线键合：引线键合（Wire Bonding）是一种使用细金属线，利用热、压力、 超声波能量为使金属引线与基板焊盘紧密焊合，实现芯片与基板间的电气互连和 芯片间的信息互通。 14. 倒装芯片：倒装芯片（Flip chip）是一种无引脚结构，一般含有电路单元。 设 计用于通过适当数量的位于其面上的锡球（导电性粘合剂所覆盖），在电气上和 机械上连接于电路。 15.热声焊：热声焊是一种固态键合技术，为热压结合与超音波结合的混合方法。 它可完成电路片与芯片、腔体之间的电连接。 16.各向异性粘接:用各向异性导电胶（主要使用单一或双重成分的环氧树脂）完 成对电路基板与倒装芯片之间的互连。 17.柔性印刷电路:即 FPC，是以聚脂薄膜或聚酰亚胺为基材制成的一种具有高度 可靠性,绝佳曲挠性的印刷电路。通过在可弯曲的轻薄塑料片上，嵌入电路设计， 使在窄小和有限空间中堆嵌大量精密元件，从而形成可弯曲的挠性电路。 18.高深宽比：垂直于加工表面的高度与其加工表面上所具有的特征尺寸的比值 大。 19. 盲孔： 定义 1.位于印刷线路板的顶层和底层表面，具有一定深度，用于表层线路和下面 的内层线路的连接，孔的深度通常不超过一定的比率（孔径）。
有限元分析报告报告材料法英文简介
The finite element analysisFinite element method, the solving area is regarded as made up of many small in the node connected unit (a domain), the model gives the fundamental equation of sharding (sub-domain) approximation solution, due to the unit (a domain) can be divided into various shapes and sizes of different size, so it can well adapt to the complex geometry, complex material properties and complicated boundary conditionsFinite element model: is it real system idealized mathematical abstractions. Is composed of some simple shapes of unit, unit connection through the node, and under a certain load.Finite element analysis: is the use of mathematical approximation method for real physical systems (geometry and loading conditions were simulated. And by using simple and interacting elements, namely unit, can use a limited number of unknown variables to approaching infinite unknown quantity of the real system. Linear elastic finite element method is a ideal elastic body as the research object, considering the deformation based on small deformation assumption of. In this kind of problem, the stress and strain of the material is linear relationship, meet the generalized hooke's law; Stress and strain is linear, linear elastic problem boils down to solving linear equations, so only need less computation time. If the efficient method of solving algebraic equations can also help reduce the duration of finiteelement analysis.Linear elastic finite element generally includes linear elastic statics analysis and linear elastic dynamics analysis from two aspects. The difference between the nonlinear problem and linear elastic problems:1) nonlinear equation is nonlinear, and iteratively solving of general;2) the nonlinear problem can't use superposition principle;3) nonlinear problem is not there is always solution, sometimes even no solution. Finite element to solve the nonlinear problem can be divided into the following three categories:1) material nonlinear problems of stress and strain is nonlinear, but the stress and strain is very small, a linear relationship between strain and displacement at this time, this kind of problem belongs to the material nonlinear problems. Due to theoretically also cannot provide the constitutive relation can be accepted, so, general nonlinear relations between stress and strain of the material based on the test data, sometimes, to simulate the nonlinear material properties available mathematical model though these models always have their limitations. More important material nonlinear problems in engineering practice are: nonlinear elastic (including piecewise linear elastic, elastic-plastic and viscoplastic, creep, etc.2) geometric nonlinear geometric nonlinear problems are caused due to the nonlinear relationship between displacement. When the object the displacement is larger, the strain and displacement relationship is nonlinear relationship. Research on this kind of problemIs assumes that the material of stress and strain is linear relationship. It consists of a large displacement problem of large strain and large displacement little strain. Such as the structure of the elastic buckling problem belongs to the large displacement little strain, rubber parts forming process for large strain.3) nonlinear boundary problem in the processing, problems such as sealing, the impact of the role of contact and friction can not be ignored, belongs to the highly nonlinear contact boundary. At ordinary times some contact problems, such as gear, stamping forming, rolling, rubber shock absorber, interference fit assembly, etc., when a structure and another structure or external boundary contact usually want to consider nonlinear boundary conditions. The actual nonlinear may appear at the same time these two or three kinds of nonlinear problems.Finite element theoretical basisFinite element method is based on variational principle and the weighted residual method, and the basic solving thought is the computational domain is divided into a finite number of non-overlapping unit, within each cell, select some appropriate nodes as solving the interpolation function, the differential equation of the variables in the rewritten by the variable or its derivative selected interpolation node value and the function of linear expression, with the aid of variational principle or weighted residual method, the discrete solution of differential equation. Using different forms of weight function and interpolation function, constitutedifferent finite element methods. 1. The weighted residual method and the weighted residual method of weighted residual method of weighted residual method: refers to the weighted function is zero using make allowance for approximate solution of the differential equation method is called the weighted residual method. Is a kind of directly from the solution of differential equation and boundary conditions, to seek the approximate solution of boundary value problems of mathematical methods. Weighted residual method is to solve the differential equation of the approximate solution of a kind of effective method. Hybrid method for the trial function selected is the most convenient, but under the condition of the same precision, the workload is the largest. For internal method and the boundary method basis function must be made in advance to meet certain conditions, the analysis of complex structures tend to have certain difficulty, but the trial function is established, the workload is small. No matter what method is used, when set up trial function should be paid attention to are the following:(1) trial function should be composed of a subset of the complete function set. Have been using the trial function has the power series and trigonometric series, spline functions, beisaier, chebyshev, Legendre polynomial, and so on.(2) the trial function should have until than to eliminate surplus weighted integral expression of the highest derivative low first order derivative continuity.(3) the trial function should be special solution with analytical solution of the problem or problems associated with it. If computing problems with symmetry, should make full use of it. Obviously, any independent complete set of functionscan be used as weight function. According to the weight function of the different options for different weighted allowance calculation method, mainly include: collocation method, subdomain method, least square method, moment method and galerkin method. The galerkin method has the highest accuracy.Principle of virtual work: balance equations and geometric equations of the equivalent integral form of "weak" virtual work principles include principle of virtual displacement and virtual stress principle, is the floorboard of the principle of virtual displacement and virtual stress theory. They can be considered with some control equation of equivalent integral "weak" form. Principle of virtual work: get form any balanced force system in any state of deformation coordinate condition on the virtual work is equal to zero, namely the system of virtual work force and internal force of the sum of virtual work is equal to zero. The virtual displacement principle is the equilibrium equation and force boundary conditions of the equivalent integral form of "weak"; Virtual stress principle is geometric equation and displacement boundary condition of the equivalent integral form of "weak". Mechanical meaning of the virtual displacement principle: if the force system is balanced, they on the virtual displacement and virtual strain by the sum of the work is zero. On the other hand, if the force system in the virtual displacement (strain) and virtual and is equal to zero for the work, they must balance equation. Virtual displacement principle formulated the system of force balance, therefore, necessary and sufficient conditions. In general, the virtual displacement principle can not only suitable for linear elastic problems, and can be used in the nonlinearelastic and elastic-plastic nonlinear problem.Virtual mechanical meaning of stress principle: if the displacement is coordinated, the virtual stress and virtual boundary constraint counterforce in which they are the sum of the work is zero. On the other hand, if the virtual force system in which they are and is zero for the work, they must be meet the coordination. Virtual stress in principle, therefore, necessary and sufficient condition for the expression of displacement coordination. Virtual stress principle can be applied to different linear elastic and nonlinear elastic mechanics problem. But it must be pointed out that both principle of virtual displacement and virtual stress principle, rely on their geometric equation and equilibrium equation is based on the theory of small deformation, they cannot be directly applied to mechanical problems based on large deformation theory. 3,,,,, the minimum total potential energy method of minimum total potential energy method, the minimum strain energy method of minimum total potential energy method, the potential energy function in the object on the external load will cause deformation, the deformation force during the work done in the form of elastic energy stored in the object, is the strain energy. The convergence of the finite element method, the convergence of the finite element method refers to when the grid gradually encryption, the finite element solution sequence converges to the exact solution; Or when the cell size is fixed, the more freedom degree each unit, the finite element solutions tend to be more precise solution. Convergence condition of the convergence condition of the finite element finite element convergence condition of the convergence condition of thefinite element finite element includes the following four aspects: 1) within the unit, the displacement function must be continuous. Polynomial is single-valued continuous function, so choose polynomial as displacement function, to ensure continuity within the unit. 2) within the unit, the displacement function must include often strain. Total can be broken down into each unit of the state of strain does not depend on different locations within the cell strain and strain is decided by the point location of variables. When the size of the units is enough hours, unit of each point in the strain tend to be equal, unit deformation is uniform, so often strain becomes the main part of the strain. To reflect the state of strain unit, the unit must include the displacement functions often strain. 3) within the unit, the displacement function must include the rigid body displacement. Under normal circumstances, the cell for a bit of deformation displacement and displacement of rigid body displacement including two parts. Deformation displacement is associated with the changes in the object shape and volume, thus producing strain; The rigid body displacement changing the object position, don't change the shape and volume of the object, namely the rigid body displacement is not deformation displacement. Spatial displacement of an object includes three translational and three rotational displacement, a total of six rigid body displacements. Due to a unit involved in the other unit, other units do rigid body displacement deformation occurs will drive unit, thus, to simulate real displacement of a unit, assume that the element displacement function must include the rigid body displacement. 4) the displacement function must be coordinated in public boundary of the adjacent cell.For general unit of coordination is refers to the adjacent cell in public node have the same displacement, but also have the same displacement along the edge of the unit, that is to say, to ensure that the unit does not occur from cracking and invade the overlap each other. To do this requires the function on the common boundary can be determined by the public node function value only. For general unit and coordination to ensure the continuity of the displacement of adjacent cell boundaries. However, between the plate and shell of the adjacent cell, also requires a displacement of the first derivative continuous, only in this way, to guarantee the strain energy of the structure is bounded. On the whole, coordination refers to the public on the border between neighboring units satisfy the continuity conditions. The first three, also called completeness conditions, meet the conditions of complete unit is complete unit; Article 4 is coordination requirements, meet the coordination unit coordination unit; Otherwise known as the coordinating units. Completeness requirement is necessary for convergence, all four meet, constitutes a necessary and sufficient condition for convergence. In practical application, to make the selected displacement functions all meet the requirements of completeness and harmony, it is difficult in some cases can relax the requirement for coordination. It should be pointed out that, sometimes the coordination unit than its corresponding coordination unit, its reason lies in the nature of the approximate solution. Assumed displacement function is equivalent to put the unit under constraint conditions, the unit deformation subject to the constraints, this just some alternative structure compared to the real structure. But the approximatestructure due to allow cell separation, overlap, become soft, the stiffness of the unit or formed (such as round degree between continuous plate unit in the unit, and corner is discontinuous, just to pin point) for the coordination unit, the error of these two effects have the possibility of cancellation, so sometimes use the coordination unit will get very good results. In engineering practice, the coordination of yuan must pass to use "small pieces after test". Average units or nodes average processing method of stress stress average units or nodes average processing method of stress average units or nodes average processing method of stress of the unit average or node average treatment method is the simplest method is to take stress results adjacent cell or surrounding nodes, the average value of stress.1. T ake an average of 2 adjacent unit stress. Take around nodes, the average value of stressThe basic steps of finite element method to solve the problemThe structural discretization structure discretization structure discretization structure discretization to discretization of the whole structure, will be divided into several units, through the node connected to each other between the units; 2. The stiffness matrix of each unit and each element stiffness matrix and the element stiffness matrix and the stiffness matrix of each unit (3) integrated global stiffness matrix integrated total stiffness matrix integrated overall stiffness matrix integratedtotal stiffness matrix and write out the general balance equations and write out the general balance equations and write out the general balance equations and write a general equation 4. Introduction of supporting conditions, the displacement of each node 5. Calculate the stress and strain in the unit to get the stress and strain of each cell and the cell of the stress and strain and the stress and strain of each cell. For the finite element method, the basic ideas and steps can be summarized as: (1) to establish integral equation, according to the principle of variational allowance and the weight function or equation principle of orthogonalization, establishment and integral expression of differential equations is equivalent to the initial-boundary value problem, this is the starting point of the finite element method. Unit (2) the area subdivision, according to the solution of the shape of the area and the physical characteristics of practical problems, cut area is divided into a number of mutual connection, overlap of unit. Regional unit is divided into finite element method of the preparation, this part of the workload is bigger, in addition to the cell and node number and determine the relationship between each other, also said the node coordinates, at the same time also need to list the natural boundary and essential boundary node number and the corresponding boundary value. (3) determine the unit basis function, according to the unit and the approximate solution of node number in precision requirement, choose meet certain interpolation condition basis function interpolation function as a unit. Basis function in the finite element method is selected in the unit, due to the geometry of each unit has a rule in the selection of basis function can follow certain rules. (4) the实用标准文案unit will be analysis: to solve the function of each unit with unit basis functions to approximate the linear combination of expression; Then approximate function generation into the integral equation, and the unit area integral, can be obtained with undetermined coefficient (i.e., cell parameter value) of each node in the algebraic equations, known as the finite element equation. (5) the overall synthesis: after the finite element equation, the area of all elements in the finite element equation according to certain principles of accumulation, the formation of general finite element equations. (6) boundary condition processing: general boundary conditions there are three kinds of form, divided into the essential boundary conditions (dirichlet boundary condition) and natural boundary conditions (Riemann boundary conditions) and mixed boundary conditions (cauchy boundary conditions). Often in the integral expression for natural boundary conditions, can be automatically satisfied. For essential boundary conditions and mixed boundary conditions, should be in a certain method to modify general finite element equations satisfies. Solving finite element equations (7) : based on the general finite element equations of boundary conditions are fixed, are all closed equations of the unknown quantity, and adopt appropriate numerical calculation method, the function value of each node can be obtained.精彩文档。
Finite Element Analysis (FEA)
Finite Element Analysis (FEA) Finite Element Analysis (FEA) is a powerful tool used in engineering and scientific fields to simulate and analyze the behavior of complex structures and systems. It is a numerical technique that breaks down a larger system into smaller, more manageable parts called finite elements. These elements are then analyzed to predict how the entire system will behave under various conditions such as stress, heat, vibration, and fluid flow. One of the key benefits of FEA is its ability to provide insight into the performance of a design without the need for physical prototyping. This can significantly reduce the time and cost involved in the product development process. Additionally, FEA allows engineers to explore a wide range of design options and make informed decisions based on the analysis results. This can lead to more efficient and optimized designs that meet performance requirements while minimizing material usage. FEA is widely used in industries such as aerospace, automotive, civil engineering, and biomechanics to analyze and improve the performance of components and systems. For example, in the aerospace industry, FEA is used to simulate the behavior of aircraft structures undervarious loading conditions, helping engineers ensure the safety and reliability of the aircraft. In the automotive industry, FEA is used to optimize the design of vehicle components such as chassis, suspension systems, and engine components to improve performance and fuel efficiency. Despite its many advantages, FEA alsohas its limitations and challenges. One of the main challenges is the need for accurate input data, such as material properties, boundary conditions, and loading conditions. Inaccurate input data can lead to unreliable analysis results, highlighting the importance of careful model setup and validation. Additionally, FEA requires specialized software and expertise to use effectively, which can be a barrier for smaller companies or organizations with limited resources. Furthermore, FEA is not a substitute for physical testing and validation. While FEA can provide valuable insights into the behavior of a design, physical testingis still necessary to verify the accuracy of the analysis results and ensure the safety and reliability of the final product. Moreover, FEA can be computationally intensive, especially for large and complex models, requiring significant computational resources and time to complete the analysis. In conclusion, FiniteElement Analysis (FEA) is a valuable tool for engineers and scientists to simulate and analyze the behavior of complex structures and systems. It offers numerous benefits such as cost and time savings, design optimization, and insight into performance without physical prototyping. However, it also comes with its own set of challenges and limitations, such as the need for accurate input data, specialized software and expertise, and the necessity of physical testing for validation. Despite these challenges, FEA remains an essential tool in the modern engineering and scientific toolkit, enabling the development of safer, more efficient, and innovative designs.。
铝合金专业英语词汇
Aquarium facility 水族馆 Cabinet 橱柜 Machinery accessories 机械配件 Grain processing 粮食加工 Purification 净化 Industrial automation equipment 工业自动化设备 Communication equipment 通信器材 Wire 天线 Bathroom 卫浴 Medical equipment 医疗设备 Scanner 扫描仪 Socket panel 插座 Automobile 汽车 Thermal chip 散热片 Nonconforming product 不合格品
专业词汇
Raw materials and semi-products 原材料和半成品: alumina 铝土 bauxite 铝矿土 log 大圆棒 bar 铝棒 billet 小圆棒（铝棒） butt 废料（挤压切头） Magnesium 镁 Silicon 硅 Iron 铁 Mill finish 素材 Industrial profile 工业异型材 Equipment 设备: log conveyor 大圆棒运输机 log furnace 大圆棒加热炉 billet furnace 铝棒加热炉 solvus temperature 溶线温度 solidus temperature 固线温度 log shear 圆棒剪 billet transveyer 铝棒运输机 press loader 挤压机托料架机械手 electrophoresis equipment 电泳设备 profile derrick 锯切机 Assembling packaging machine 组角机 Vertical motion geophone 立式铣床 Radial drilling machine 摇臂钻床 Direct-reading spectrometer 直读式光谱仪 Electronic universal testing machine 电子万能试 验机 UV test 紫外光测试 Q-SUN weathering test machine Q-SUN 耐候试验 机 Vickers hardness Tester 盐雾测试仪 Metallographic micro-hardness tester 金相显微 硬度计 Salt spray test 维氏硬度计 Vacuum heat treatment furnace 真空热处理炉 Round melting furnace 圆形炉 Cooling chamber 冷却炉 In-line degassing 在线除气 Electronic magnetic stir machine 电磁搅拌机 ram 挤压杆 dummy block 压饼（挤压垫） container 盛锭筒 container liner 盛锭筒内衬（内套） runout table 输出台 front platen 前板 main cylinder 主缸 Anodizing equipment 氧化设备 Double-ended cutter 双头切割机床 Double head copy lathe 双头仿铣床 Punching machine 冲床 Vertical drilling machine 立式钻床 Rib circular drilling machine 攻牙机 Colorimeter 色差仪 Gloss meter 光泽计 Scanner 扫描仪 QUV climate simulations tester QUV 气候模拟测 试仪 Cupping tester 杯突试验仪 Webster hardness tester 韦氏硬度计 Rockwell hardness tester 洛式温度计 Shakeout testing machine 落砂试验机 Vortex thickness gauge 涡流测厚仪 Tilting melting furnace 倾翻炉 Homogenizing furnace 均质炉 Air-slip casting table 气模 Automatic cutting machine 自动据台 Optical microscope analyzer 金相分析仪 Steel 钢 Copper 铜 Manganese 锰 Chromium 铬 extrudability 可挤压性 strength-to-weight ratio 强度重量比 quenching 淬火 conductivity 可导电性，导电率 Ingot 铝锭 Flat sheet 铝板 Profile 异型材
机械类常用英语
机械类常用英语引言随着全球化的推进，机械类行业在国际间的交流与合作越来越频繁。
掌握常用的机械类英语词汇和短语，对于从事机械类行业的专业人士来说至关重要。
本文将介绍机械类常用英语，助您更好地与国际同行进行沟通和合作。
一、机械设计和工程1.1 机械设计常用词汇•Machine（机器）: A device that uses power to apply forces and control movement to perform a task.•Mechanism（机构）: A system of moving parts that work together to achieve a certn function.•Component（零件）: A part or element that makes up a larger mechanical system.•Assembly（装配）: The process of putting together components to form a complete machine.•Drafting（制图）: The act of creating technical drawings to communicate design specifications.•Tolerance（公差）: The allowable variation in measurements or dimensions of a component or assembly.•CAD（Computer-ded Design，计算机辅助设计）: The use of computer software to create and modify designs.1.2 机械工程常用短语•Structural analysis（结构分析）: The study of the behavior and performance of structures under different loads and conditions.•Material selection（材料选择）: The process of choosing the most suitable materials for a given application.•Finite element analysis（有限元分析）: A numerical method used to analyze the behavior of complex structures.•Flure analysis（失效分析）: The investigation of the causes of mechanical flures and the development of solutions to prevent future flures.•Performance optimization（性能优化）: The process of improving the efficiency and effectiveness of a mechanical system.•Prototyping（原型制作）: The creation of a physical model or representation of a design for testing and evaluation.•Quality control（质量控制）: The process of ensuring that products meet specified quality standards.•Safety regulations（安全规定）: The laws and regulations that govern the use and operation of machinery to ensure safety.二、机械制造和加工2.1 机械制造常用词汇•Manufacturing（制造）: The process of converting raw materials into finished products through various operations.•Machining（机械加工）: The process of shaping a workpiece by removing material using tools such as lathes, milling machines, and drills.•Casting（铸造）: The process of pouring molten metal or liquid material into a mold to create a solid object.•Welding（焊接）: The process of joining two or more pieces of metal by heating them to their melting point and allowing them to cool and fuse together.•Grinding（磨削）: The process of removing material from a workpiece using an abrasive wheel or belt.•CNC（Computer Numerical Control，数控）: The use of computer-ded control systems to operate and control machine tools. •Tooling（工装）: The specialized tools and equipment used in manufacturing processes.•Automation（自动化）: The use of machines or computer systems to perform tasks without human intervention.2.2 机械加工常用短语•Cutting speed（切削速度）: The speed at which a cutting tool moves through a workpiece during machining.•Feed rate（进给速度）: The rate at which the cutting tool advances into the workpiece during machining.•Depth of cut（切削深度）: The distance between the cutting tool and the surface of the workpiece during machining.•Surface finish（表面光洁度）: The quality and smoothness of a machined surface. •Chip removal（切屑排出）: The process of removing chips or waste material generated during machining.•Tool life（刀具寿命）: The length of time a cutting tool can be used before it becomes dull and needs to be replaced.•Heat treatment（热处理）: The process of heating and cooling a material to alter its properties and improve its performance.•Dimensional accuracy（尺寸精度）: The degree to which a machined part conforms to its specified dimensions.三、机械维护和保养3.1 机械维护常用词汇•Mntenance（维护）: The process of keeping equipment in good working condition to ensure reliability and prevent breakdowns.•Lubrication（润滑）: The application of a lubricant to reduce friction and wear between moving parts.•Inspection（检查）: The systematic examination of equipment to detect and correct any defects or problems. •Troubleshooting（故障排除）: The process of identifying and resolving problems or malfunctions in mechanical systems. •Preventive mntenance（预防性维护）: The scheduled mntenance activities performedto prevent equipment flure and prolong its lifespan.•Breakdown mntenance（故障维修）: The repr activities performed in response to unexpected equipment flures.3.2 机械保养常用短语•Routine mntenance（定期保养）: The regular inspection, cleaning, and adjustment of equipment to ensure its efficient operation.•Lubrication schedule（润滑计划）: The predetermined intervals at which lubrication should be applied to equipment. •Replacement parts（更换零件）: The components or parts that need to be replaced during mntenance and repr.•Calibration（校准）: The process of adjusting or setting equipment to ensure accuracy and reliability.•Equipment downtime（设备停机时间）: The period of time during which equipment is not operational due to mntenance or repr.•Safety precautions（安全注意事项）:The measures and procedures to be followed to ensure the safety of mntenance personnel.结论机械类常用英语对于机械类行业从业者来说至关重要。
毕设翻译原文
Heat transfer simulation in drag–pick cutting of rocksJohn P. Loui , U.M. Rao Karanama .Central Mining Research Institute, Barwa Road, Dhanbad, Jharkhand , Indiab .Department of Mining Engineering, Indian Institute of Technology, Kharagpur , IndiaAbstractA two-dimensional transient heat transfer model is developed using finite element method for the study of temperature rise during continuous drag-cutting. The simulation results such as temperature built-up with time and maximum stabilized pick–rock interface temperature are compared with experimental results for various input parameters. The effect of frictional force and cutting speed on the temperature developed at the pick–rock interface is also studied and compared with the experimental observations.Keywords: FEM; Rock cutting; Heat transfer; Wear1. IntroductionAll the rock cutting operations involve rock fracturing and subsequent removal of the broken rock chips from the tool–rock interface and drag –picks are one of the many types of cutting tools used for cutting rocks in rock excavation engineering. They are versatile cutting tools and have proved to be more efficient and desirable for cutting soft rock formations. However,there is a continuous effort to extend their applications to all types of rock formations.The forces responsible for rock fracture under the action of a drag-cutter can be resolved into two mutually perpendicular directions viz., thrust (normal) force Fn and cutting (tangential) force Fc. It is the cutting force,which decides the specific energy requirement for any cutting operation.Amajor part of the total energy spent during drag-cutting is lost as frictional heat. The temperature rise at the pick–rock interface due to this frictional heat has a significant effect on the wear rate of the cutting tool. Gray et al.(1962),De Vries (1966), Roxborough (1969), Barbish and Gardner (1969), Estes (1978), Detournay and Defourny (1992), Cools (1993), Loui and Rao (1997) found that the higher temperatures encountered in tool–rock interaction ultimately results in drastic reduction in drag-bit performance. It may also cause significant thermal stresses in rock as well as the tool. The experimental investigations conducted earlier (De Vries, 1966; Estes, 1978;Karfakis and Heins, 1966; Loui and Rao, 1997;Martin and Fowell, 1997) could only measure pick–rock interface temperatures at 2–3 locations on the cutting tool.Most of the temperature measurements during laboratory experiments were done by thermocouples placed within the tool. Conducting such experiments is not onlytime consuming and costly but also provide inadequate information if the objective is to study the temperature distribution in the pick–rock system.Analytical modelling for predicting the temperature during rock cutting requires major simplification of the problem and this may not be able to provide accurate results for the complicated real life situation of drag-cutting.Therefore, a numerical modelling technique viz., the finite element method is used in the current study to develop a two dimensional transient heat transfer model to solve for the temperature profile in the pick –rock system.The present paper discusses the development of this transient heat transfer model and its experimental validation.2.Theoretical heat transfer analysis in drag-cuttingPrior to the finite element solution of the problem,theoretical analysis has been done to evaluate input parameters for the finite element program. These parameters include velocity field in the pick–rock system,forces acting on the rake and flank face of the drag-cutter and the heat generated due to the interfacial friction while cutting.2.1. Velocity fieldsFor simplicity, the drag-cutting process is simulated as the pick remaining stationary against the rock moving past the cutter at a cutting velocity Vc. The resulting velocity fields in the uncut rock and fully formed chip are evaluated theoretically as input parameters for the numerical model.Though the researchers in the past have postulated linear (Nishmatsu, 1972) and curvilinear (Loui, 1998)paths of rock failure during the process of chip formation,for simplicity, it is assumed to be linear for the evaluation of velocity fields in the chip and the uncut rock. Fig. 1 illustrates this process of chipping under the action of a drag-cutter. The failure path is linear and at an angle / with respect to the cutting velocity as shown in Fig. 1. The inter-relationships between the cutting velocity Vc, shear velocity along the shear plane Vs, and chip velocity along the rake face Vr are represented in Fig. 2. These velocity fields in the rock areevaluated relative to the pick and thus the pick domain is assumed to be stationary against a moving rock domain.It has been found from chip-formation simulation studies (Loui, 1998) that the fracture plane (shear plane)exists at an angle of 30–35 with respect to the cutting velocity.From the velocity diagram (Fig. 2), the velocity components,u and v in x and y directions respectively, for the uncut rock and fullyformed chip are given by the following Eqs. (1) and (2), respectively. Uncut rocku =V c and v =0 （1）Fully formed chipu =γsin r V and v =γcos r V （2）2.2. ForcesThe forces acting on an orthogonal drag-cutter are representeddiagrammatically in Fig. 1. The cutting force Fc and the thrust force Fn were measured experimentallyand are related to the normal and frictional forces at the rake face and flank face (N and F, and /N and /F , respectively) as shown below: ,sin cos /c F F F F ++=γγ (3),sin cos /n N N F F +-=γγ (4)If μ is the tool –rock interface friction,//NF N F ==μ, (5)Solving for N and /N , we get,γμγμμsin ,2cos )1(2+--=N C F F N (6) γμγμγγμγμγsin 2cos )1()sin cos ()sin cos (2/+---+=C N F F N , (7) 2.3. Heat generationHeat generation during drag-cutting is mainly caused by friction at the interface between the pick and the rock (at flank and rake faces) as the cutter is dragged againstthe rock surface at a certain cutting velocity.It requires large or repeated plastic deformations to result in heat generation as in the case of metal cutting.Though elasto-plastic deformations take place in certainrock types before their failure and the formation of chips, suchdeformations are not large enough in rocks to result in the generation of heat. Therefore, for the purpose of estimating the heat generation during dragcutting,the rock chipping can be assumed to be caused by brittle failure and the heat generation limited to frictional heating. ）（c f r V N NV Q Q Q /r tot +=+=μ， （8）where Qr and Qf are the frictional heat generated per second (watts) at the rake and flank faces, respectively,and Vr and Vc are the interfacial chip velocity at the rake face and flank face respectively.The velocity at which rock slides along the rake face of the tool (Vr) after rock chipping is difficult to assess.A fully formed chip does not offer a force against the rake face of the tool since it is completely detached from the rock mass and gets thrown away during the process of cutting. It has been observed by researchers in the past that drag tools undergo severe flank wear (wear land) and insignificant wear of the cutting face (Pliset al., 1988). Hence, for all practical purposes, the heat generated due to tool –rock friction at the rake face could be ignored and Eq. (8) reduces toV N Q Q f /tot μ==， （9）3. Discretization of pick –rock systemSince a simple orthogonal cutting tool is considered,heat transfer in the pick –rock system is treated as a two-dimensional problem by ignoringthe end effects.The whole domain has been discretized and analyzed in a two-dimensional Cartesian coordinate system. In the finite element solution of the problem, the domain is discretized into four-noded isoparametric elements as shown in Fig. 3. In the cutting simulations the pick is assumed to be stationary, thus the spatial discretizationof the pick does not change with time. However,since the rock is assumed to move past the pick at a constant velocity Vc, the discretized domain in the rock changes with time as per the velocity fields evaluated above.4. Finite element formulationGalerkin s approach has been used for converting the thermal energy equation (Eq. (10)) into a set of equivalent integral equations,tT C Q y T V X T C y T T K P P ∂∂=+∂∂+∂∂-∂∂+∂∂ )()x (2222μ， （10） where k is the coefficient of thermal conductivity, q is the density and Cp is the specific heat capacity at constant pressure.Let T be the approximate solution temperature and Rfem the finite element residue. Then, fem 2222-)()x (R tT C Q y T V X T C y T T K P P =∂∂+∂∂+∂∂-∂∂+∂∂ μ， （11） The approximate temperature solution T can be represented over the solution domain by[][]n T N T = ， （12）where [N] is the overall shape function vector and {Tn} is the nodal temperature vector. With the use of Eq. (12), Eq. (11) can be discretized (Shih, 1984) yielding,5. Laboratory micro-pick experimentsThe cutting action was simulated using laboratory scale micro-picks and the rotary drag-cutting was carried out against an applied vertical thrust force. The applied thrust levels (Fn) were in the range of 230–750 N and the cutting speeds (Vc) were 0.01, 0.16 and 0.25m/s, which are within the practical drag-cutting ranges.The experiments were conducted on a vertical drill machine. A schematic diagram of the complete experimental setup is shown in Fig. 4. Laboratory scale micro-picks used for rotary cutting had tungsten carbide inserts as the cutting edge. The inserts were 12 mm in length, 10 mm in width and 3.5 mm in thickness and was designed to have a wedge angle of 80 and a rake angle of 10. For the measurement of temperature developed during cutting, copper–constantan thermocouple was introduced into a 1-mm diameter hole drilled at a distance of 2 mm from the cutting edge within the tungsten carbide insert and blazed with silver to secure a good holding. The micro-picks along with thermocouple are given in Fig. 5.A pre-calibrated milli-voltmeter of the range 0.1–1000 mV was used to record the difference of voltage across the thermocouple. Torque generated at the pick–rock interface is measured using a spoked wheelTorque generated at the pick–rock interface is measured using a spoked wheel dynamometer (Rao and Misra, 1994) in line with arecorder.In all these experiments, the drag–pick cutter was held stationary between the plates of the dynamometer and the rock core samples were held in a holder. The rock sample holder is designed to hold samples at one end, while the other end is provided with a taper, which fits into the drill shank. With this arrangement, rock core sample rotates against the stationary drag –pick during the cutting process. The pick-holder and rockholder are shown in Fig. 6. The experimental results have been discussed, in details, in Loui and Rao(1997). However, only a few of the experimental results are used in this paper for validation of the numerical model.6. Results and discussionThe numerical model developed in the current study has the ability to predict the pick–rock interfacial temperature and the temperature profiles in the pick–rock system. The main input parameters, which influence the temperature development at the pick–rock interface, are the cutting speed and the interfacial friction at the flank face ofthe pick. Eq. (9) shows they are linearly related to the quantity of heat generated at the pick–rock interface. The results obtained from the numerical model are compared with those observed from the experimental observations.6.1. Temperature built-upAll the simulation runs indicated that after 6 minute of pick–rock contact time, the temperature through out the domain stabilizes.Pick-rock interface temperature is defined as the average interface temperature observed along the flank face of the tool and is evaluated using Eq. (23). The temperature rise with time at the pick–rock interface for the rock type sandstone at a cutting speed of 0.25 m/s, thrust force of 230 N, and for a depth of cut of 1 mm is shown in Fig. 7. A comparison is also made with the experimental observation of the pick–rock interface temperature for the same input parameters used for the numerical model. The trend by which temperature builds up and further stabilizes has been found to be in a good agreement with the experimental observations. This trend is due to the fact that the amount of the heat generated being much higher during the onset of the cutting process compared to the dissipation of heat. As the cutting proceeds, the temperature builds up in the pick –rock system. When the temperature attains higher regimes, the heat dissipation due to convection and conduction also increases and eventually equals the heat generation due to friction. As the rate of heat generation remains constant, provided the machine operating parameters are unaltered, the temperature in the pick–rock system tends to stabilize after a few minutes of cutting.6.2 Stabilized interface temperatureThe stabilized pick–rock interface temperature at the end of 6 min of continuous cutting is termed as the stabilized interface temperaturefor that particular simulationor experiment. The variation of the stabilized pick–rock interface temperature has been studied against some of the input parameters, which directly influence the temperature such as the cutting speed and the frictional force. Other parameters like depth of cut, rake angle, etc. influence the frictional force at the interface and therefore, have only indirect effect on the temperature developed.Fig. 9 shows the variation of stabilised interfacial temperature with the cutting speed and its comparison with the experimental observation. The input parametersfor the numerical model were taken corresponding to the operating parameters used for the experiments. The predicted values by FEM analysis show a linear variation(Fig. 9) since the cutting speed is directly proportional to the quantity of heat generated (Eq. (9)).The other parameter, which directly influences the heat generation at the pick–rock interface, is the frictional force at the flank face of the pick and therefore,it has been plotted against the pick rock interface temperature for numerical and experimental results (Fig.10). As observed from Fig. 10, both the results show aLineartrend.In general, from all the temperature prediction runs,the numerical results showed a higher temperature values(up to approximately 25%) compared to their experimentalcounterparts. In the numerical model it has been assumed that all of the frictional heat generated at the flank face of the tool has been converted into frictional heat which may be the reason for an over estimation. However, the errors incurred in the experimental dragcutting and also during observation using thermo-couple type of temperature measurement system cannot totally be ignored. Martin and Fowell (1997) has measured the pick–rock interface temperature using thermocouples as well as infra-red gun and found that the latter recorded higher temperature values. The error incurred may be partly due to the two-dimensional approximation of drag-cutting.6.3. Temperature variation along rake face and flankfaceFigure 11 shows the temperature variation at its stabilized state (after 6 min of continuous cutting period) along rake face and flank face of the tool. Both the curves (flank and rake faces) are plotted simultaneouslystarting from the tip of the cutter, which is the intersection point for both the forces. As frictional heat is generate at the wear-land of the flank face of the tool,temperature rises along the wear land reaches a maximum approximately at the mid point of the wear land (hf), and drops rapidly towards the flank side of the cutter as show in Fig. 11. Since at the rake face of the tool no heat is being generated during cutting, temperature falls along the rake face from the tool edge.This indicates that the temperature concentration takes place at the worn-out portion of the flank face of the cutting tool (wear land), which comes in direct contact with the rock.7.ConclusionsA general purpose finite element program has been developed to study the temperature attained during pick–rock interaction. The model has been used forthe prediction of pick–rock interface temperatures as well as temperature profile of the whole pick–rock System.The transient heat transfer modelling showed that the temperature builds up steeply during the onset of cutting and stabilizes within a few minutes of continuous pick–rock contact. This trend has been validated from experimentalobservations.The results obtained from the numerical model proves direct effect of the rock cutting parameters viz., frictional force and cutting velocity on the temperaturerise at the pick–rock interface. This has been validated by linearly increasing trends observed between the stabilized interface temperature and the rock cuttingParameters.The current study has dealt with continuous dragcutting,both numerically and experimentally. However,the transient finite element program developed can bemodified to predict the temperature rise in the pick during intermittent cutting, which mostly occurs in real life cutter picks used in road headers and shearers. With theprior knowledge of frictional forces acting in the pick–rock system during intermittent cutting, this modification can be done by suppressing the heat generationterms and adding convective heat transfer terms at the pick–rock interface nodes when the pick leaves the contact with the rock; and by initialization of rock domaintemperatures and re-introduction of heat generation terms duringre-contact. Since the experimental setup used in the current study was not designed for intermittentcutting, experimental data could not be obtained for validation and therefore, intermittent cutting was not dealt in this paper. Further, it may require a moredetailed three-dimensional modelling to reduce the errors and to get the results closer to the realistic temperature values.ReferencesBarbish, A.B., Gardner, G.H.F., 1969. The effect of heat on some mechanical properties of igneous rocks. ASME J. Soc. Petr. Eng. 9,395–402.Cools, P.C.B.M., 1993. Temperature measurements upon the chisel surface during rock cutting. Int. J. Rock Mech. Min. Sci. Geomech.30, 25–35.De Vries, M.F., 1966. Investigation of drill temperature as a drilling performance criterion. Ph.D. thesis, University of Wisconsin, USA.Detournay, E., Defourny, P., 1992. A phenomenological model for the drilling action of drag bits. Int. J. Rock. Mech. Min. Sci. 29, 13–23. Estes, J.C., 1978. Techniques of pilot scale drilling research. ASME J. Pressure Vessels Technol. 100, 188–193.Gray, K.E., Armstrong, F., Gatlin, C., 1962. Two-dimensional study of rock breakage in drag-bit drilling at atmospheric pressure. J. Pertol. Technol., 93–98.Karfakis, M.G., Heins, R.W., 1966. Laboratory investigation of bit bearing temperatures in rotary drilling. ASME J. Energy Resourc.Tech. 108, 221–227.Loui, J.P., Rao, K.U.M., 1997. Experimental investigations of pick –rock interface temperature in drag–pick cutting. Indian J. Eng.Mater. Sci. 4, 63–66.Loui, J.P., 1998. Finite element simulation and experimental investigationof drag-cutting in rocks. Ph.D. thesis, Indian Institute of Technology, Kharagpur, India.Martin, J.A., Fowell, R.J., 1997. Factors governing the onset of severe drag tool wear in rock cutting. Int. J. RockMech. Min. Sci. 34, 59–69. Nishmatsu, Y., 1972. The mechanics of rock cutting. Int. J. Rock Mech. Min. Sci. 9, 261–272.Plis, M.N., Wingquist, C.F., Roepke, W.W., 1988. Preliminary Evaluation of the Relationship of Bit Wear to Cutting Distance, Forces and Dust Using Selected Commercial and ExperimentalCoal and Rock Cutting Tools. USBM, RI-9193, p. 63.Rao, K.U.M., Misra, B., 1994. Design of a spooked wheel dynamometer. Int. J. Surf. Mining Recl. 8, 146–147.Roxborough, F.F., 1969. Rock cutting research. Tunnels Tunnelling 1, 125–128.Shih, T.M., 1984. Numerical Heat Transfer. Hemisphere/Springer, Washington/New York, p. 563.。
abaqus二维切削结论 -回复
abaqus二维切削结论-回复以下是一篇关于Abaqus二维切削的论文，旨在回答中括号内的主题。
文章将逐步探讨切削力、切屑形成、表面质量和切削温度等方面的内容，并提供相关的研究成果和实证数据。
【Abaqus二维切削结论】- 深入探讨切削过程的关键要素引言：切削是机械加工中常见的一种加工方法，通过将刀具与工件接触并运动，去除工件的材料以达到所需形状和尺寸。
切削过程涉及多种力学现象，如切削力、切屑形成、表面质量和切削温度等。
通过使用Abaqus软件可以更好地研究和模拟这些过程，以帮助工程师和研究人员更好地理解和优化切削操作。
1. 切削力切削力是切削过程中最重要的力学参数之一。
它直接影响切削的稳定性、切削负载和工件的表面质量。
Abaqus软件可以模拟和计算切削过程中的切削力。
通过建立合适的切削模型，设置切削速度、进给速度和刀具几何参数等，可以模拟不同条件下的切削力曲线。
研究结果表明，切削力随着切削速度和进给速度的增加而增加，根据不同的材料和切削条件，切削力的变化规律可能会有所不同。
2. 切屑形成切屑是切削过程中生成的废料，对切削过程的质量和效率有着很大的影响。
Abaqus软件可以通过模拟切削过程来研究切屑形成的机理。
研究发现，切屑形态和切屑类型都与切削速度、进给速度和切削深度等参数有关。
较高的切削速度和进给速度可能导致螺旋切削形态的切屑，而较低的切削速度和进给速度可能导致纤维状切屑。
更高的切削深度可能导致切削力的增加和切屑的断裂。
3. 表面质量切削表面质量是切削过程中一个非常重要的指标，它直接影响工件的使用寿命和性能。
Abaqus软件可以通过模拟切削过程来评估表面质量。
研究发现，切削速度、进给速度和切削深度等参数对表面质量有着重要影响。
较高的切削速度和进给速度会产生较大的切削力和切削温度，进而导致表面质量的降低。
较大的切削深度也会导致表面质量的降低。
4. 切削温度切削温度是切削过程中一个非常重要的参数，它直接影响刀具寿命和工件表面质量。
finite element procedures in engineering analysis
finite element procedures inengineering analysisFinite element procedures, also known as finite element analysis (FEA), are numerical techniques used in engineering analysis to simulate and solve complex problems involving structures, mechanical systems, and other physical phenomena. These procedures are based on the discretization of a continuum or a geometrical domain into a finite number of elements, interconnected at nodes.The primary goal of finite element procedures is to predict the behavior of a system under various loading conditions and boundary constraints. By breaking down the problem into smaller elements, the equations governing the behavior of the system can be formulated and solved using matrix-based numerical methods.One of the key advantages of finite element procedures is their ability to handle complex geometries and boundary conditions. They can be applied to structures with irregular shapes, holes, or curved surfaces, which would be challenging to analyze using traditional analytical methods. Additionally, finite element procedures allow for the simulation of a wide range of physical phenomena, including structural deformation, heat transfer, fluid flow, and electromagnetic fields.During the finite element analysis, a mesh is generated, which represents the discretized domain. The mesh consists of elements with defined shapes, such as triangles or quadrilaterals in 2D and tetrahedra or hexahedra in 3D. The nodes at the intersections of elements serve as points where the system's unknown variables, such as displacements or temperatures, are defined.Once the mesh is created, the governing equations, such as the equilibrium equations in structural analysis or the heat conduction equation in thermal analysis, are formulated for each element. These equations are then assembled into a global system of equations, which can be solved using numerical techniques, such as the Gaussian elimination or iterative methods.The results of the finite element analysis provide valuable insights into the behavior of the system, including stress distributions, deformations, temperature gradients, or fluid velocities. These results can be visualized d and analyzed to assess the performance, reliability, and safety of engineering designs.In summary, finite element procedures are essential tools in engineering analysis, allowing engineers to simulate and predict the behavior of complex systems with high accuracy. These procedures provide valuable insights into the performance and design优化 of various engineering structures and phenomena.。
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specializing in the development, production, and sales of single-axisand multi-axis linear module, motion controllers industrial equipment.LINEAR MOTION SYSTEM INTELLIGENTPRODUCTS MANUFACTURER3.0LTD 关于我们/ABOUT US P01-08公司简介研发技术生产工艺品质检验客户与案例公司资质产品概述产品详情/PRODUCT DESCRIPTION P09-89 FSK模组FSL系列模组FBL系列模组FPB系列模组FTH系列模组FTB系列模组二轴直角坐标机器人三轴直角坐标机器人定制工作台控制器配件选型我们的服务/OUR SERVICE P90-92售前技术售后服务FUYU TECHNOLOGY CO.,成都福誉科技有限公司成立于2011年11月，专注于直线运动系统的研发、生产、销售和服务。
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“福誉科技”已获国家相关部门认证：“国家高新技术企业”，“双软企业”，ISO9001-2015，知识产权管理体系，知识产权已授权82项，涉及发明专利6项，实用新型、外观专利及软件著作权76项；已获国际相关认证：德国莱茵机构“TUV”认证，及CE, ROHS FCC Ip等级认证。
福誉产品已辐射全球90余个国家，福誉人秉持“真实、担当、持续精进”的价值观，不断迭代优化产品和服务获取与更多合作伙伴的共赢。
Chengdu Fuyu Technology Co., Ltd. was established in November 2011, focusing on the research and development, production, sales and service of linear motion systems. We continue to introduce high-end talents and improve the industrial chain cluster. At the same time, we attach great importance to the mode of production-university- research cooperation with universities and research institutes, and sincerely cooperate with domestic and foreign powerful brand enterprises.FUYU Technology has been certified by relevant national departments: "National High-tech Enterprise", "Double Soft Enterprise", ISO9001-2015, Intellectual Property Management System, 82 intellectual property rights have been authorized, involving 6 invention patents, utility model, appearance patents and 76 software copyrights; The products also have obtained international certifications, such as German Rheinland organization "TUV" and CE, ROHS, FCC, IP66, etc.Fuyu's products have been sold to more than 90 countries around the world, we uphold the values of "Authentic, Responsible and Keep Improving", constantly iteratively optimize products and services to get win-win opportunities with more partners.国家高新技术企业双软企业National High-Tech Enterprise D o u b l e S o f t E n t e r p r i s e专利认证patent certificates一带一路重点推荐企业One Belt One Road Highly Recommeded Enterprise智造商industry qualification certificationsaccumulated coverage companies知识产权82项资质认证19项产品辐射国家地区96个累计客户资源12K个intellectual property rights年均增长幅度146cover 96 countries and regionsSales growth位于成都的福誉科技研发中心，从设备的结构有限元分析，材料分析到加工工艺、装配技术、检测方式、智能软件、底层算法等。
numerical methods in finite element analysis
numerical methods in finite element analysis Numerical Methods in Finite Element AnalysisIntroductionFinite Element Analysis (FEA) is a widely used numerical method for solving engineering problems. It involves dividing a complex geometry into simple elements and solving equations to determine the behavior of the structure under different loading conditions. Numerical methods are essential in FEA as they provide efficient and accurate solutions to complex problems. This article will discuss the numerical methods used in FEA.1. Basics of Finite Element AnalysisFEA involves dividing a complex geometry into simple elements such as triangles or rectangles. Each element is defined by a set of nodes and equations are solved at these nodes to determine the behavior of the structure. The equations are usually based on the principle of virtual work, which states that the work done by external forces on a structure is equal to the internal work done by stresses within the structure.2. Types of ElementsThere are different types of elements used in FEA, including linear, quadratic, and cubic elements. Linear elements have straight edges, while quadratic and cubic elements have curved edges. The choice of element depends on the complexity of the geometry and accuracy required for analysis.3. Numerical IntegrationNumerical integration is used to evaluate integrals that arise in FEA equations. The most commonly used integration methods include Gauss-Legendre quadrature and Newton-Cotes formulas such as trapezoidal rule and Simpson's rule.4. Matrix ManipulationThe equations generated from FEA are usually represented in matrix form, which requires manipulation using matrix algebra techniques such as inversion, multiplication, andaddition/subtraction.5. Solution TechniquesThere are different solution techniques used in FEA, including direct solvers, iterative solvers, and preconditioners. Direct solvers involve solving the entire system of equations at onceusing matrix inversion techniques such as LU decomposition or Cholesky factorization. Iterative solvers involve solving the system one equation at a time using iterative methods such as Jacobi or Gauss-Seidel. Preconditioners are used to improve the convergence rate of iterative solvers.6. Boundary ConditionsBoundary conditions are essential in FEA as they define the behavior of the structure at its boundaries. The most commonly used boundary conditions include fixed boundary conditions, which prevent movement in a particular direction, and symmetry boundary conditions, which assume that the structure is symmetric about a plane.7. Mesh GenerationMesh generation is the process of dividing a complex geometry into simple elements for FEA analysis. There are different mesh generation techniques, including structured meshing, unstructured meshing, and adaptive meshing.8. Error EstimationError estimation is essential in FEA as it provides an indication of the accuracy of the solution. The most commonly used errorestimation techniques include residual-based error estimation and recovery-based error estimation.ConclusionIn conclusion, numerical methods are essential in Finite Element Analysis as they provide efficient and accurate solutions to complex engineering problems. The choice of numerical method depends on the complexity of the geometry and accuracy required for analysis. Understanding these methods is crucial for successful application of FEA in engineering design and analysis.。
出国成绩单课程名称中英文对照参考表
外国文学作选读Selected Reading of Foreign Literature现代企业管理概论Introduction to Modern Enterprise Managerment电力电子技术课设计Power Electronics Technology Design计算机动画设计3D Animation Design中国革命史China’s Revolutionary History中国社会主义建设China Socialist Construction集散控制DCS Distributed Control计算机控制实现技术Computer Control Realization Technology计算机网络与通讯Computer Network and CommunicationERP/WEB应用开发Application ＆ Development of ERP/WEB数据仓库与挖掘Data Warehouse and Data Mining物流及供应链管理Substance and Supply Chain Management成功心理与潜能开发Success Psychology & Potential Development信息安全技术Technology of Information Security图像通信Image Communication金属材料及热加工Engineering Materials & Thermo-processing机械原理课程设计Course Design for Principles of Machine机械设计课程设计Course Design for Mechanical Design机电系统课程设计Course Design for Mechanical and Electrical System。
国际新型电池前沿技术交流会2012
44杨金丽等：银含量对随机振动条件下无铅焊点可靠性的影响V ol.31No.9 Sep. 2012与IMC层的硬度差异较大，在振动过程中，由于电路板与BGA封装的刚度不同，焊点反复承受拉压应力的交替作用，最终在硬脆的IMC界面处产生裂纹并快速扩展，导致焊点失效。
这应该是SAC305比SAC105和SAC0307抗振性弱的另一个原因。
另外，从图10上可以看出，SAC305的金属间化合物呈颗粒状断续分布，颗粒与颗粒之间有许多小的间隙，一旦裂纹开始萌生后，会沿这些间隙迅速扩展，并有可能沿着间隙向焊料球基体内部扩展，如图10（a）所示，而SAC105和SAC0307的金属间化合物呈连续的片层状，如图10（b）和10（c）所示。
内部基本没有间隙，裂纹萌生以后，沿着IMC 与焊盘的界面处扩展，由于没有相当于小裂纹的间隙存在，使得裂纹的萌生和扩展需要的时间都比SAC305长得多。
这也是低银钎料比高银钎料抗振性好的另一个原因。
3结论（1）随着Ag含量的降低，焊点的抗振动疲劳寿命逐渐提高。
（2）在低银钎料的IMC前端吸附了许多纳米级Ag3Sn粒子，Ag3Sn粒子的形成有利于降低(Cu，Ni)6Sn5IMC颗粒的表面能，抑制界面IMC的生长。
但过高的Ag含量会导致Sn的活度降低，也会降低界面反应速率，使生成的界面IMC厚度减小，另外，Ag3Sn粒子的富集使得IMC层与焊料球基体之间的过渡区硬度增大，减小了它们之间的硬度差异。
（3）Ag含量较低的SAC0307和SAC105金属间化合物呈连续的片层状分布，较为致密，而Ag含量较高的SAC305的金属间化合物呈颗粒状分布，内部有很多细小的间隙，这些间隙很容易成为裂纹源或使裂纹沿这些间隙扩展，导致焊点快速失效。
参考文献：[1] 杜长华, 陈方, 杜云飞. Sn-Cu、Sn-Ag-Cu系无铅钎料的钎焊特性研究[J]. 电子元件与材料, 2004, 23(11): 33-36.[2] EVELOYV G, FUKUD A Y. Are you ready for leadfree electronics? [J].IEEE Trans Compon Packg Technol, 2005, 28(4): 884-894.[3] SUNDELIN J J, NURMI S T, LEPISO T K, et al. Mechanical andmicrostructural properties of SnAgCu solder joints [J]. Mater Sci Eng A, 2006, 420(1/2): 55-62.[4] 尹立孟, 位松, 李望云. 电子封装用低银含量无铅钎料的研究和应用进展 [J]. 焊接技术, 2011, 40(5): 1-5.[5] LIGUORE S, FOLLOWELL D. Vibration fatigue of surface mounttechnology(SMT)solder joints [J]. IEEE Proc Ann Reliab Maintainability Symp, Am, 1995: 18-26.[6] Institute for Clinical and Economic Review Waste. Electronic andelectrical equipment [M]. UK: [s.n.], 2000.[7] JEIDA. Challenges and efforts toward commercialization of lead freesolder road map 2000 for commercialization of lead free solder [M].Japan: Japan Electronic Industry Development Association, 2000.[8] GRIEU M, MAIRE O, MASSIOT G, et al. Sn3.0Ag0.5Cu solder jointslife time estimation for electronic assemblies under random vibration[C]// Electronic System Integration Technology Conference (ESTC2008). London: University of Greenwich, 2008.[9] GRIEU M, MASSIOT G, MAIRE O, et al. Durability modeling of BGAcomponent under random vibration [C]// Proceedings of 9th Int Conf on Thermal, Mechanical and Metaphysics Simulation and Experiments in Micro-Electronics and Micro-Systems. USA: IEEE, 2008.[10] PERKINS A, SITARAMAN S K. Analysis and prediction of vibrationinduced solder joint failure for a ceramic column grid array package [J]. J Electron Packg, 2008, 130(1): 011012, 1-11.[11] CHE F X, PANG J H L. Vibration reliability test and finite elementanalysis for flip chip solder joints [J]. Microelectron Reliab, 2009, 49(7): 754-760.[12] PITARRESI J M, PRIMVERA A A. Comparison of modeling techniquesfor the vibration analysis of pr inted circuit cards [J]. ASME J Electron Packag, 1992, 114(4): 378-383.[13] 白洁. 跌落/冲击过程中电子封装焊锡接点的动力学响应 [D]. 北京:北京工业大学, 2007.[14] 周新. 板级无铅焊点跌落冲击载荷下可靠性分析 [D]. 上海: 上海交通大学, 2007.[15] 李晓延. 金属间化合物对SnAgCu/Cu界面破坏行为的影响 [J]. 机械强度, 2005, 27(5): 666-671.[16] 何大鹏. 合金元素对二元Sn基钎料钎焊界面IMC的影响 [D]. 大连:大连理工大学, 2005.（编辑：陈渝生）国际新型电池前沿技术交流会（CIBF2012）在深圳召开由中国电子学会化学与物理电源技术分会、中国化学与物理电源行业协会主办的国际新型电池前沿技术交流会（CIBF2012）近日在广东省深圳市隆重召开。
超硬材料行业常见英文单词
Diamond Blade 金刚石刀片Dicing Saw 划片Saw Street 划片街区DI water 去离子水Chipping 崩角chip 芯片FSC- Front Side Chipping 正面崩角BSC-Back Side Chipping 背面崩角Seal Ring 密封环Mounting tape承载薄膜Wafer 硅片,晶片Reticle 掩膜Bonding pad 焊线区Single cut 单刀切割Step cut 台阶式切割Emphatically 着重Resin 树脂Grinding 磨削optoelectronics 光电子ultrathin 超薄superabraive 超硬材料mounting 安装substrate 基体spindle 主轴rotate 旋转tangential stress 切向应力radial stress 径向应力finite element analysis 有限元分析three-dimensional modeling 三维建模chip 切屑matrix 结合剂diamond concentration 金刚石浓度grits size 粒度Blade dress 刃具修正Machining 加工optimized优化，最佳diameter 直径rigid 刚性的adhesive 胶黏feed rate 进给速度cutting speed 切割线速度ratio 比值margin 边缘solder ball 焊料球inspection检测specification 规格规范coat 涂层debris 碎屑yield 产率；产量oxygen plasma 氧等离子体particle 颗粒wax 蜡solvable 可溶解的uniformity 均匀性augment 增大。
机械电子工程专业课程设置一览表
64
64
0
理学院
4
A3
B2
C2C4
复变函数
Complex Function
2.0
32
32
理学院
4
A3
B2
C2C4
大学物理（甲）
College Physics（A）
5
80
80
理学院
2
A3
B2
B3
C3C4
大学物理实验（甲）
College Physics Experiments (A)
1.5
48
48
综合
实践
工程训练（甲）
Engineering Training(B)
2.0
4周
必修
机电
学院
2
A1A4
A5
B1B2
B3B4
C1C2
C3C4
电子工艺实习（乙）
Electronic Technical Practice（B）
1.0
1周
必修
机电
学院
3
A6
B6B8
B9
C5C6
C7
机械原理课程设计
Course Design of Mechanisms and Machine Theory
表1机械电子工程专业课程设置一览表
课程类型
课程
编号
课程名称
学分
总
学
时
学时
分配
必修/选修
开设
学院
开设学期
知识
贡献
能力
贡献
素质
贡献
讲课
实验
通识类(40.9%)65.5学分类
思想
CP03_6 Finite Element Analysis
n
x xi
Ci
The coefficients are just the potentials at special points. define the basis function for element ei as
x y
e i e i e i e i
(i: basis function or grid point index)
K ij K ji i j d i j d
k 1 k n
K ij 0
i j 1
(2) The coefficients == the potentials
x xi
C i i
i 1
n
x xi
C i i
2
Second step:
C ii [C ]
i 1
7
n
Numerical solution:
1 0
2
0.5V |1 g 0.5V
( x 1) ( x 1)
It is symmetric, define the finite elements as
x xi
Ci
6
Finite element method First step:
K ij K ji
local
i j d
K C f b
1
g
jd fj local 0
b j h j d
C 1.0 0.98 0.92 0.68 0.5
T
16
Accurate solution: