Reflow soldering temperature curve
Reflow profile 解读
怎样设定锡膏回流温度曲线
接下来必须决定各个区的温度设定，重要的 是要了解实际的区间温度不一定就是该区的显 示温度。显示温度只是代表区内热敏电偶的温 度，如果热电偶越靠近加热源，显示的温度将 相对比区间温度较高，热电偶越靠近PCB的直 接通道，显示的温度将越能反应区间温度。
怎样设定锡膏回流温度线
典型PCB回流区间温度设定 区间 预热
RTS温度曲线可用于任何化学成分或合金，为水溶锡膏和难 于焊接的合金与零件所首选。 RTS温度曲线比RSS有几个优 点。RTS一般得到更光亮的焊点，可焊性问题很少，因为在 RTS温度曲线下回流的锡膏在预热阶段保持住其助焊剂载体 。这也将更好地提高湿润性，因此，RTS应该用于难于湿润 的合金和零件。
得益于升温-到-回流的回流温度曲线
得益于升温-到-回流的回流温度曲线
升温-保温-回流 RSS温度曲线开始以一个陡坡温升，在90秒的目标 时间内大约150° C，最大速率可达2~3° C。随 后，在150~170° C之间，将装配板保温90秒钟； 装配板在保温区结束时应该达到温度均衡。保温 区之后，装配板进入回流区，在183° C以上回 流时间为60(± 15)秒钟。
理解锡膏的回流过程
2.
3.
助焊剂活跃，化学清洗行动开始， 水溶性助焊剂和免洗型助焊剂都会 发生同样的清洗行动，只不过温度 稍微不同。将金属氧化物和某些污 染从即将结合的金属和焊锡颗粒上 清除。好的冶金学上的锡焊点要求 “清洁”的表面。 当温度继续上升，焊锡颗粒首先单 独熔化，并开始液化和表面吸锡的 “灯草”过程。这样在所有可能的 表面上覆盖，并开始形成锡焊点。
升温-到-回流
因为RTS曲线的升温速率是如此受控的，所以 很少机会造成焊接缺陷或温度冲击。另外， RTS曲线更经济，因为减少了炉前半部分的加 热能量。此外，排除RTS的故障相对比较简单， 有排除RSS曲线故障经验的操作员应该没有困 难来调节RTS曲线，以达到优化的温度曲线效 果。
MTS 垂直平面编码器和潜在电阻器说明书
EncodersMetalShaft Insulated Shaft Hollow Shaft Ring TypeThe following parts are included with the product.Nut Washer11M9×0.752ø14ø9.10.520mm Size Metal Shaft Type / Attached Parts20mm Size Metal Shaft Type / Switch SpecificationsSwitch type Momentary push switchContact arrangementSingle pole and single throw （Push-on）Travel（mm） 1.5±0.5Operating force 4±2N Operating life20,000 timesElectrical performanceRating0.5A 16V DC (1mA 16V DC min. ratings）Contact resistance 100mΩ max. for initial period, 200mΩ max. after operating life.Insulation resistance 100MΩ min. 250V DCVoltage proof300V AC for 1 minute or 360V AC for 2sUnit:mmCircuit Diagram（RK203）23120mm Size Metal Shaft Type EC20A RK203EC111Incremental （Two phase A and B）EncodersMetalShaftInsulated ShaftRing TypeHollowShaftSoldering surfacetemperatureSoldering temperatureHeating timeSoldering timeNo. of soldersEC10E, EC12D, EC12E, EM11B EC45A EC40A EM20BEC09E, EC11B, EC111, EC11E, EC11G,EC11K, EC18A, EC21A, EC28A, EC35A, EC35AH, EC35B, EC50A, EC60B Series100℃ max.260±5℃2 min. max.5±1s2 time max.100℃ max.100℃ max.110℃ max.80℃ max.260±5℃260℃ max.260℃ max.260℃ max.1 min. max.2 min. max.1 min. max.1 min. max.3±1s 5s max.10s max.3s max.2 time max.2 time max.1 time 2 time max.PreheatingDip solderingReference for Dip SolderingExample of Reflow Soldering ConditionReference for Manual SolderingEC05E EC21CEC11J Series 260℃230℃180℃150℃ 2 min. max.3s 40s 4 min. max.2 time max.250℃ min.230℃ to 245℃230℃ min.220℃180℃200℃150℃150℃60s to 120s 60s to 120sーー30s to 40s 25s to 60sー300 max.2 time max.1 time max.ABCDEFGHNo. of reflowsTemperature profile1. When using an infrared reflow oven, solder may sometimes not be applied. Be sure to use a hot air reflow oven or a type that uses infrared rays in combination with hot air.2. The temperatures given above are the maximum temperatures at the terminals of the encoder when employing a hot air reflow method. The temperature of the PC board and the surface temperature of the encoder may vary greatly depending on the PC board material, its size and thickness. Ensure that the surface temperature of the encoder does not rise to 250℃ or greater.3. Conditions vary to some extent depending on the type of reflow bath used. Be sure to give due consideration to this prior to use.注記300200100A BC Time (s)G max.F max.H max.E max.RoomtemperatureT e m p e r a t u r e (˚C )Pre-heating DEncoders Soldering Conditions3 s EC11JEC05E, EC09E, EC10E, EC111, EC11B, EC11E, EC11G, EC11K, EC12D, EC12E, EC18A, EC21A, EC28A, EC35A, EC35AH, EC35B, EC40A, EC45A, EC50A, EC60B, EM11B, EM20B, EC21C Series350℃ max.3s max. 1 time350±10℃2 timeTip temperatureSoldering timeNo. of solders＋1 0。
258 Encoders 金属杆壳型绝对类型 EC18A 水抗性强、重力扭矩强 18mm 尺寸 金属
259EncodersMetal ShaftInsulatedShaftThroughShaft TypeRing TypeStandard Codes 1. The ●marks shows the ON position.2. The ●marks ： Connections between terminals and the 5 （COM） are ON.Waterproof PropertyImmersion of encoder, not in operation, in water at depth of 1m at normal temperature for 30 minutes.EC18AGAPosition No.123456789101112Rotation angle （° ）3060901201501802102402703003301●●●●●●2●●●●3●●●●●●4●●●●5（COM ）●●●●●●●●●●●●T E R M I N A L N O .EC18AGB20401Position No.12345678910111213141516Rotation angle （° ）22.54567.590112.5135157.5180202.5225247.5270292.5315337.51●●●●●●●●2●●●●●●●●3●●●●●●●●4●●●●●●●●5（COM ）●●●●●●●●●●●●●●●●T E R M I N A L N O .EC18AGB20407Position No.123456789101112131415Rotation angle （° ）244872961201441681922162402642883123361●●●●●●●●2●●●●●●●●3●●●●●●●●4●●●●●●●●5（COM ）●●●●●●●●●●●●●●●T E R M I N A L N O .EC18A ／18mm Size Insulated Shaft Type（Two phase A and B ）275EncodersMetal ShaftInsulated Shaft Through Shaft TypeRing Type1. When using an infrared reflow oven, solder may sometimes not be applied. Be sure to use a hot air reflow oven or a type that uses infrared rays in combination with hot air.2. The temperatures given above are the maximum temperatures at the terminals of the encoder when employing a hot air reflow method. The temperature of the PC board and the surface temperature of the encoder may vary greatly depending on the PC board material, its size and thickness. Ensure that the surface temperature of the encoder does not rise to 250℃ or greater.3. Conditions vary to some extent depending on the type of reflow bath used. Be sure to give due consideration to this prior to use.NotesEC05E EC21CEC28C, EC35CH250℃ min.230℃ to 245℃260℃230℃ min.220℃ 230℃180℃200℃180℃150℃150℃150℃60s to 120s 60s to 120s 2 min. min.ーー3s30s to 40s 25s to 60s40sー300s max.230s max.2 times max.1 time max.1 time max.Soldering surfacetemperatureSoldering temperatureHeating timeSoldering timeNo. of soldersEC09E, EC111, EC11E, EC11M, EC11N, EC18A,EC21A, EC28A, EC35A, EC35AH, EC50A Series100℃ max.260±5℃2 min. max.5±1s 2 times max.PreheatingDip solderingReference for Dip SolderingExample of Reflow Soldering ConditionReference for Manual SolderingEC10E, EC12D, EC12E EM11BEC40A100℃ max.100℃ max.110℃ max.260±5℃260℃ max.260℃ max.1 min. max.1 min. max.1 min. max.3±1s 3s max.10s max.2 times max.2 times max.1 timeTemperature profile300200100A BC Time (s)G max.F max.H max.E max.RoomtemperatureT e m p e r a t u r e (˚C )Pre-heating DEncoders / Soldering ConditionsEC05E, EC09E, EC10E, EC111, EC11E, EC11M, EC11N, EC12D, EC12E, EC18A, EC21A, EC28A, EC35A, EC35AH, EC40A, EC50A, EM11B, EC21C, EC28C, EC35CHSeries350℃ max.3s max. 1 timeTip temperatureSoldering timeNo. of soldersSeries ABCDEFGHNo. of reflows。
回流焊常见缺陷的分析解读
南京信息职业技术学院毕业设计论文作者王浩学号*****P29 系部机电学院专业电子组装技术与设备(通信设备制造) 题目回流焊常见缺陷的分析指导教师谭淑英高晴评阅教师完成时间：2014年05月15 日目录1引言 (1)2 影响回流焊焊接质量的因素 (1)2.1 PCB焊盘设计 (1)2.2焊膏质量 (1)2.3物料的质量和性能 (2)2.4焊接过程工艺控制 (2)3回流焊常见缺陷及解决措施 (3)3.1锡珠 (3)3.2芯吸 (5)3.3曼哈顿现象 (5)3.4桥连 (6)3.5空洞 (8)3.6 PCB扭曲 (8)结论 (9)致谢 (9)参考文献 (10)1引言表面贴装(SMT)技术作为新一代电子装联技术已经渗透到各个领域，SMT产品具有结构紧凑、体积小、耐振动、抗冲击，高频特性好、生产效率高等优点。
典型的SMT工艺分为三步：施加焊锡膏——贴装元器件——回流焊接，回流焊接技术作为SMT三大主要工艺之一，其焊接品质已成为影响电子组装直通率的关键因素，尤其是在电子产品向无铅化、微小化和高密度方向发展的时代，回流焊是SMT技术中非常关键的步骤。
在回流焊接过程中对焊接缺陷的控制，对于SMT产品质量起着至关重要作用。
2 影响回流焊焊接质量的因素2.1 PCB焊盘设计回流焊的焊接质量与PCB焊盘设计有直接的的关系。
如果PCB焊盘设计正确,贴装时少量的歪斜可以在回流焊时由于熔融焊锡表面张力的作用而得到纠正(称为自定位或自校正效应)；相反，如果PCB焊盘设计不正确，即使贴装位置十分准确，回流焊后反而会出现元件位置偏移、吊桥等焊接缺陷。
PCB焊盘设计要注意：（1）两端焊盘必须对称，以保证熔融焊锡表面张力平衡；（2）焊盘间距要能确保元件端头或引脚与焊盘恰当的搭接尺寸，焊盘间距过大或过小都会引起焊接缺陷（如表1)；表1 0201焊盘设计尺寸（3）元件端头或引脚与焊盘搭接Array后的剩余尺寸必须保证焊点能够形成弯月面；（4）焊盘宽度应与元件端头或引脚的宽度基本一致。
Reflow技术要求及测试方法
Reflow技术要求及测试方法回流温度曲线的一般技术要求及测试方法一、回流温度曲线在生产中地位：回流焊接是在SMT工业组装基板上形成焊接点的主要方法，在SMT工艺中回流焊接是核心工艺。
因为表面组装PCB的设计，焊膏的印刷和元器件的贴装等产生的缺陷，最终都将集中表现在焊接中，而表面组装生产中所有工艺控制的目的都是为了获得良好的焊接质量，如果没有合理可行的回流焊接工艺，前面任何工艺控制都将失去意义。
而回流焊接工艺的表现形式主要为回流温度曲线，它是指PCB的表面组装器件上测试点处温度随时间变化的曲线。
因而回流温度曲线是决定焊接缺陷的重要因素。
因回流曲线不适当而影响的缺陷形式主要有：部品爆裂/破裂、翘件、锡粒、桥接、虚焊以及生半田、PCB脱层起泡等。
因此适当设计回流温度曲线可得到高的良品率及高的可靠度，对回流温度曲线的合理控制，在生产制程中有着举足轻重的作用。
二、回流温度曲线的一般技术要求及主要形式：1．回流温度曲线各环节的一般技术要求：一般而言，回流温度曲线可分为三个阶段：预热阶段、回流阶段、冷却阶段。
预热阶段：预热是指为了使锡水活性化为目的和为了避免浸锡时进行急剧高温加热引起部品不具合为目的所进行的加热行为。
•预热温度：依使用锡膏的种类及厂商推荐的条件设定。
一般设定在80～160℃范围内使其慢慢升温（最佳曲线）；而对于传统曲线恒温区在140～160℃间，注意温度高则氧化速度会加快很多（在高温区会线性增大，在150℃左右的预热温度下，氧化速度是常温下的数倍，铜板温度与氧化速度的关系见附图）预热温度太低则助焊剂活性化不充分。
•预热时间视PCB板上热容量最大的部品、PCB面积、PCB厚度以及所用锡膏性能而定。
一般在80～160℃预热段内时间为60～120see，由此有效除去焊膏中易挥发的溶剂，减少对元件的热冲击，同时使助焊剂充分活化，并且使温度差变得较小。
•预热段温度上升率：就加热阶段而言，温度范围在室温与溶点温度之间慢的上升率可望减少大部分的缺陷。
5050 0.5W规格书
Color bin limit(If=150mA)—◎white
色区范围(IF=150mA) —白光
Bin
X
Y
Bin
X
Y
Bin
0.283 0.284
0.3035 0.332
0.295 0.297
0.315 0.3435
A0
A7
B4
0.298 0.288
0.316 0.332
0.287 0.276
0.306 0.322
Y 0.357 0.3697 0.3568 0.345 0.369 0.3827 0.3697 0.357 0.3812 0.3956 0.3827 0.369 0.321 0.342 0.332 0.3135 0.342 0.355 0.3435 0.332
White CIE Chromaticity Diagram
Our 5050 products, use silica gel packages, effectively improve the heat dissipation performance. Reliability is better than companies in general, it is a complete white combination with high brightness, low-light decay characteristics.
0.316 0.332
0.329 0.33
0.317 A6
0.308
0.319 0.311
0.329 0.345 B3
0.3455 0.3568
0.306 0.322
0.3442 0.3421
X 0.329 0.3466 0.3455 0.329 0.329 0.3478 0.3466 0.329 0.329 0.3489 0.3478 0.329 0.287 0.301 0.3035 0.2895 0.301 0.314 0.315 0.3035
回流焊炉温曲线的管控分析
基金项目:广西重点研发计划项目"全息电子工业制程云数据分析平台"(2017AB19031)；广西高等教育本科教学改革工程项目"信息管理与信息系统专业'互联网+'能力培养的研究与实践"(2016JGB125)、"基于校企互动的《IT 项目管理》课程MOOC 建设与研究"(2018GJB107)作者简介:汤宗健(1968-)，男，副教授，硕士，主要从事信息系统与数据分析研究。
通信作者简介:谢炳堂(1968-)，男，侗族，高级工程师，大学本科，主要从事电子制造工作。
回流焊炉温曲线的管控分析Management and Control Analysis of Reflow Soldering Furnace Temperature Curve汤宗健1,谢炳堂2,梁革英1(1.广西大学数学与信息科学学院,广西南宁530004;2.南宁富桂精密工业有限公司,广西南宁530031)Tang Zong-jian 1,Xie Bing-tang 2,Liang Ge-ying 1(1.College of Mathematics and Infor-mation Science,Guangxi University,Guangxi Nanning 530004;2.Nanning Fugui Precision Industrial Co.,Ltd,Guangxi Nanning 530031)摘要：回流焊温度曲线记录印刷电路板元件焊接过程的温度变化，是元件焊接质量的主要影响因素。
针对用测温板获取回流焊温度曲线的影响因素，对测温流程进行潜在失效效应分析，发现利用测温板频繁进行炉温测试具有较高的风险系数。
但通过对回焊炉各温区温度的监控与分析，发现回焊炉的制程能力处于优良状态，潜在失效效应的风险系数较低。
研究表明，在获取可靠的炉温曲线后，只需要加强炉温监控即可保证焊接质量。
回流焊接温度曲线优化的机理建模研究
回流焊接温度曲线优化的机理建模研究作者：孙昊晟张金珠来源：《科技创新导报》2021年第14期摘要：在回流焊工藝中，如何加热可使得回焊炉各温区的温度变化保持工艺要求，对产品质量至关重要。
目前，这方面的许多工作是通过实验测试来进行控制和调整的。
本文通过对回焊炉中对电子元件的传热过程的机理进行分析，建立了回流焊接过程中电路板焊接区域中心的温度随时间变化的机理模型;进一步以电子元件在回流焊期间最大热应力为优化目标，创新性地定义了炉温曲线对称性评价指标，以“炉温曲线中超过峰值的‘尖端区’覆盖的面积最小且左右对称”为目标函数，采用启发式遗传算法计算得到最优炉温曲线，与相应的参数设定值。
研究结果为回流焊实际生产的参数设置提供了参考，具有较强的工程实践意义。
关键词：回流焊炉温曲线机理模型对称性评价指标优化中图分类号：TN405 文献标识码：A文章编号：1674-098X（2021）05（b）-0066-07Research on the Mechanism Model of Reflow Soldering Temperature Profile OptimizationSUN Haosheng ZHANG Jinzhu*（Hebei University of Technology， Tianjin， 300401 China）Abstract： In the reflow soldering process， maintaining the best reflow furnace temperature is essential to product quality. At present， many researches in this area are carried out through experimental tests. This paper analyzes the mechanism of the heat transfer process in the reflow furnace， and establishes a mechanism model of the temperature change in the center of the soldering area of the circuit board during the reflow soldering process; Then， innovatively defined the evaluation index of the symmetry of the furnace temperature curve. Furthermore， the heuristic genetic algorithm is applied to calculate the optimal furnace temperature curve and the corresponding parameters. The results provide a reference for the parameter setting of the reflow soldering， and have strong engineering practical significance.Key words： Reflow furnace temperature curve; Mechanism model; Symmetry evaluation index; Optimization在电子元件表面组装工艺（SMT）中，回流焊是实现印制板与元器件的冶金结合的关键工序[1-3]。
工厂中SMT制程段生产中常用英文
工厂中SMT制程段生产中常用英文In the manufacturing industry, Surface Mount Technology (SMT) is a popular method for electronic component assembly. It is widely used in factories around the world for its efficiency and accuracy. In this article, we will explore the commonly used English terms and phrases in SMT production.1. PCBA (Printed Circuit Board Assembly)PCBA refers to the process of assembling electronic components onto a printed circuit board (PCB). It includes soldering, solder paste printing, component placement, and reflow soldering.2. Solder Paste PrintingSolder paste is a mixture of solder alloy and flux. In the SMT process, solder paste is printed onto the PCB using a stencil. This is an important step to ensure proper alignment and solder joint quality.3. StencilA stencil is a metal or polymer sheet with openings that correspond to the positions of the components on the PCB. It is used to apply solder paste onto the board during the printing process.4. Pick and Place MachineA pick and place machine is used to place the electronic components onto the PCB accurately. It can handle different component sizes and shapes. This machine uses robotic arms and a vision system to ensure precise placement.5. Reflow SolderingReflow soldering is the process of melting the solder paste to create a permanent solder joint between the components and the PCB. The PCB with the components is passed through a furnace that heats it up to the soldering temperature.6. Soldering Temperature ProfileThe soldering temperature profile is a set of temperature values and durations that specify the heating and cooling process during reflow soldering. It ensures proper solder joint formation and prevents component and PCB thermal damage.7. SMD (Surface Mount Device)SMDs are electronic components that are designed to be mounted directly onto the surface of a PCB. They are small in size and have no lead wires. SMDs include resistors, capacitors, integrated circuits, and many other electronic devices.8. Moisture Sensitivity Level (MSL)MSL is a measure of how sensitive an SMD is to moisture absorption. Components with higher MSL ratings require special handling and storage conditions to avoid damage during soldering.9. InspectionInspection is an essential part of SMT production to ensure the quality of the assembly. It includes visual inspection for solder joint defects, automated optical inspection (AOI) to detect component placement errors, and X-ray inspection to check for hidden defects.10. Defect Detection and RepairIn SMT production, defects can occur during the printing, placement, or soldering processes. Defect detection systems are used to identify defective components or solder joints. Repairs are then made to correct the defects and ensure the functionality of the final product.11. ESD (Electrostatic Discharge) ProtectionESD is the sudden transfer of an electric charge between two objects. In the SMT production environment, ESD can damage sensitive electronic components. Therefore, proper ESD protection measures, such as the use of grounding straps and anti-static mats, are essential.12. Test and MeasurementAfter the PCBA is completed, it undergoes testing to ensure that it meets the required specifications. Testing may include functional testing, in-circuit testing (ICT), and boundary scan testing. Measurements are taken to verify the electrical characteristics and performance of the assembled board.In conclusion, SMT production in a factory involves various processes and techniques. This article has covered the commonly used English terms and phrases in SMT production, providing a basic understanding of the key stages and concepts. Having a good grasp of these terms will help both workers and managers communicate effectively and efficiently in an SMT production environment.SMT生产是电子制造业中常用的组装技术之一。
en reflow 最全回流焊中英对照表
led积分球仪器， led流明仪， 色温测试仪， led光谱仪led integrating sphere instrument, led lumens meter, color temperature tester, led spectro 回流炉因为不同的工作方式分2种原来的叫做 IR oven。
IR是加热方式现在的叫 reflow oven， 热风回流方式市面上也有混合型号的，也叫 reflow oven。
简单点叫reflow大家也懂Reflow soldering1. Fundamentals of Solders and Soldering（焊料及焊接基础知识）Soldering Theory（焊接理论）Microstructure and Soldering（显微结构及焊接）Effect of Elemental Constituents on Wetting（焊料成分对润湿的影响）Effect of Impurities on Soldering（杂质对焊接的影响）2. Solder Paste Technology（焊膏工艺）Solder Powder ( 锡粉)Solder Paste Rheology（锡膏流变学）Solder Paste Composition & Manufacturing（锡膏成分和制造）3. SMT Problems Occurred Prior to Reflow（回流前S Flux Separation（助焊剂分离)Paste Hardening（焊膏硬化）Poor Stencil Life（网板寿命问题)Poor Print Thickness（印刷厚度不理想）Poor Paste Release From Squeegee（锡膏脱离刮刀问题）Smear（印锡模糊）Insufficiency（印锡不足）Needle Clogging（针孔堵塞）Slump（塌落）Low Tack（低粘性）Short Tack Time （粘性时间短）4. SMT Problems Occurred During Reflow（回流过程中的SMT问题）Cold Joints（冷焊）Nonwetting（不润湿）Dewetting（反润湿）Leaching（浸析）Intermetallics（金属互化物）Tombstoning（立碑）Skewing（歪斜）Wicking（焊料上吸）Bridging（桥连）Voiding（空洞）Opening（开路）Solder Balling(锡球)Solder Beading（锡珠）Spattering（飞溅）5. SMT Problems Occurred at Post Reflow Stage（回流后问题）White Residue（白色残留物）Charred Residue（炭化残留物）Poor Probing Contact（探针测接问题）Surface Insulation Resistance or Electrochemical Migration Failure（表面绝缘阻抗或电化迁移缺陷）Delamination/Voiding/Non-curing Of Conformal Coating/Encapsulants（分层 / 空洞 / 敷形涂覆或包封的固化问题）6. Challenges at BGA and CSP Assembly and Rework Stage （BGA、CSP组装和翻修的挑战）Starved Solder Joint（少锡焊点）Poor Self-Alignment（自对位问题）Poor Wetting（润湿不良）Voiding（空洞）Bridging（桥连）Uneven Joint Height（焊点高度不均）Open（开路）Popcorn and Delamination（爆米花和分层）Solder Webbing（锡网）Solder Balling（锡球）7. Problems Occurred at Flip Chip Reflow Attachment（倒装晶片回流期间发生的问题）Misalignment（位置不准）Poor Wetting（润湿不良）Solder Voiding（空洞）Underfill Voiding（底部填充空洞）Bridging（桥连）Open（开路）Underfill Crack（底部填充裂缝）Delamination（分层）Filler Segregation（填充分离）Insufficient Underfilling（底部填充不充分）8. Optimizing Reflow Profile via Defect Mechanisms Analysis （回流曲线优化与缺陷机理分析）Flux Reaction（助焊剂反应）Peak Temperature（峰值温度）Cooling Stage（冷却阶段）led spectrometer工艺）ior to Reflow（回流前SMT问题）问题）。
最新无铅制程培训资料
Lead-Free Manufacturing Engineering Training module for TechniciansChinese RevTranslated By: HUA-ME Lead Free teamOct, 2004A dvanced M anufacturing E ngineeringLead (Pb) Free’s Background, why to apply Lead free (推行无铅化的背景, 为什么要推行无铅化)Pb is harmful for Human’s health and environment(铅对环境及人体健康是有害的)Marketing and Legislative require to apply Lead (Pb) free, Especially in Electronic and Equipment.(市场及立法机构要求推行无铅化, 尤其是在电子电气设备中.EU (European Union) requires to meet Rohs requirement from Jul.1,2006. Including Pb Free requirement(欧盟要求从2006年7月1日起在电子电气设备中禁止使用包括铅在内的六种有害物质)Industry standard for Lead Free is Less than 0.1% Pb by weight in a products.(无铅的现有工业判定标准是产品中铅含量必须小于产品重量的0.1%.Lead Free’s impact and affect to Electronics industry(无铅化对电子电气工业的冲击与影响)Solder material (焊接材料)Solder material have to change from Sn/Pb alloy to Sn/Ag/Cu or Sn/Cu alloy mainly.(焊接材料不得不从以锡铅合金为主转向以锡银铜合金或锡铜合金为主.)Solder material changing lead to the overall changing and impact in Electronics Industry, due to high solderingtemperature of SAC alloy.(因为锡银铜合金的高焊接温度导致电子工业的全面转变与影响)From Component manufacturing and PCB assembly process, it has to do compatible changing for Lead Free(从元件制造到PCB组装制程, 不得不作出同无铅化相一致与兼容的变更) Viewpoint from different aspect, we can say the root impact and change is sourced from the High soldering temperature(从某种不同的角度看, 我们可以说根本性的冲击与变更来源于焊接高温)EMS PCB Assembly production(电子制造服务PCB组装生产)Conception of PCB Assembly production(PCB组装生产的概念)To solder Component on PCB with solder material at high temperature.(在高温条件下, 用焊接材料将元件焊接到印制电路板上)PCB (print circuit board) (印制电路板)Component (元件)Solder material (焊料)Conception of PCB Assembly production(PCB组装生产的概念)Component (元件)SMD Component(表面贴装元件)THT Component(通孔元件)Conception of PCB Assembly production (PCB组装生产的概念)Solder paste on PCB (印制电路板的焊接材料--锡膏)Conception of PCB Assembly production (PCB组装生产的概念)Soldering (焊接)Conception of PCB Assembly production (PCB组装生产的概念)PCBA (印制电路板组装件)Lead Free’s soldering temperature profile (无铅回流焊接的温度曲线)Lead Free’s reflow soldering temperature profile(无铅回流焊接的温度曲线)Reflow soldering requirement for Sn3~4Ag0.5Cu:(锡银铜类无铅合金锡膏的回流焊接要求)SAC Alloy’s melting point:217C~220C(锡银铜合金的熔点: 217C~220C)Reflow Time above Melting point to peak temperature 235~245C: 45s~120s(高于熔点温度到峰值235C~245C的回流焊接时间: 45~120秒)Reflow Time above 230C for solder joint: Minimum 10s(高于230度的焊点回流焊接时间: 最少维护持10秒)Sn/Pb’s reflow soldering temperature profile (锡铅合金回流焊接的温度曲线)Sn/Pb’s reflow soldering temperature profile(锡铅合金回流焊接的温度曲线)Reflow soldering requirement for Sn63/Pb37 orSn62/36Pb/Ag2:(锡铅类有铅合金锡膏的回流焊接要求)Sn/Pb Alloy’s melting point:183C(锡铅合金的熔点: 183C)Reflow Time above Melting point to peak temperature 210~225C: 30s~90s(高于熔点温度到峰值210C~225C的回流焊接时间: 30~90秒)Compare reflow soldering temperature between Sn/Pb and Sn/Ag/Cu:(比较锡铅合金与锡银铜合金回流焊接的温度曲线)45~120s30~90sReflow timeabove Meltpoint(高于熔的回流焊接时间)Increase 25C (增加25度)235~245C210~225CPeaktemperature(峰值温度)Increase 37C (增加37度)220C183CAlloy melt point(合金熔点)Result(结果)Sn/Ag/Cu(锡银铜合金)Sn/Pb(锡铅合金)Item(项目)Lead Free’s wave soldering temperature profile (无铅波峰焊接的温度曲线)Lead Free’s wave soldering temperature profile(无铅波峰焊接的温度曲线)Wave soldering requirement for Sn3~4Ag0.5Cu:(锡银铜类无铅合金锡膏的回流焊接要求)SAC Alloy’s melting point:217C~220C(锡银铜合金的熔点: 217C~220C)Wave Time above Melting point to peak temperature 250~260C: 2s~4s(高于熔点温度到峰值250C~260C的波峰焊接时间: 2~4秒)Sn/Pb’s wave soldering temperature profile (有铅波峰焊接的温度曲线)Sn/Pb’s wave soldering temperature profile (有铅波峰焊接的温度曲线)Actual wave soldering temperature profile sample245C180s183CSn/Pb’s wave soldering temperature profile(有铅波峰焊接的温度曲线)Wave soldering requirement for Sn63Pb37:(锡铅类含铅合金锡巴的波峰焊接要求)SnPb Alloy’s melting point:183C(锡铅合金的熔点: 183C)Wave Time above Melting point to peak temperature 240~250C: 2s~4s(高于熔点温度到峰值240C~250C的波峰焊接时间: 2~4秒)Compare Wave soldering temperature between Sn/Pb and Sn/Ag/Cu:(比较锡铅合金与锡银铜合金波峰焊接的温度曲线)2~4s2~4sReflow timeabove Meltpoint(高于熔点的回流焊接时间)Increase 10C (增加10度)255~260C250CPeaktemperature(峰值温度)Increase 37C (增加37度)220C183CAlloy melt point(合金熔点)Result(结果)Sn/Ag/Cu(锡银铜合金)Sn/Pb(锡铅合金)Item(项目)Requirement for PCB (无铅化对PCB的要求)Print Circuit Board(印制电路板)surface finishes 可接受的PCB (金属)表面处理 Ni-Au (镍-金)OSP Cu(Organic Solderability Preservative)(铜表面涂有机可焊性保护膜)immersion Silver-Imm Ag (沉银) immersion Tin-Imm Sn (沉锡)Board laminate (PCB 板材)Most Board laminate construction materials are compatible (大部分PCB 的基材是兼容(无铅)制程要求的)Recommended board laminate material for use in “high-end”applications (I.E. severs) to have:(推荐满足高端应用要求的PCB 的基材具有下述性能☺High glass transition temperature (Tg)高玻璃转化温度(Tg))High decomposition temperature (高分解温度(Td))备注: PCB 板材及表面处理的选择是有其应用规范的.Requirement for PCB (无铅化对PCB 的要求)表面处理列表Component Considerations 对元件无铅化方面的考虑Terminal and Ball metallurgies (元件焊接终端与焊球金属要求)Terminal and Ball metallurgies(元件焊接终端与焊球金属要求)元件焊接终端与焊球金属Component package: JEDEC 020C MSL 元件封装要求: 湿度敏感元件级别建议的020C 封装级别相应的温度表4-1 针对锡铅共晶合金制程(Process)---含铅元件封装可耐受的回流焊接峰值温度225+0/-5 C225+0/-5 C>=2.5 mm225+0/-5 C 240+0/-5 C <2.5 mm 体积(mm^3) >=350体积(mm^3) <350元件封装厚度建议的020C 封装级别相应的温度表4-1 针对锡铅共晶合金制程(Process)---元件封装可耐受的回流焊接峰值温度JEDEC 020C 湿度敏感元件级别*公差: 元件制造商/提供商应该确保其元件达到其声明的湿度敏感元件耐高温级别.建议的020C 封装级别相应的温度表4-2 针对无铅合金制程(Process)---元件封装可耐受的回流焊接峰值温度245 C *245 C *250 C *>2.5 mm245 C *250 C *260 C *1.6mm~2.5mm 260 C *260 C *260 C *<1.6 mm 体积(mm^3) >2000体积(mm^3) 350~2000体积(mm^3) <350元件封装厚度不同元件封装的耐高温分类级别当维持最低230C的焊点(solder Joint)温度时, 一些关键重要的元件封装温度将在020C 封装级别相应的温度之上.元件外包装标贴(Label)的考虑在创建回流焊接温度曲线(Profile)之前,确信检查过敏感元件的湿度敏感级别(MSL)元件或许是无铅的, 但是也许其湿度敏感级别(MSL)较低元件外包装标贴(Label)的考虑元件外包装标贴(Label)的考虑在元件外包装标贴上有明显的Pb free 标识元件外包装标贴(Label)的考虑在元件外包装标贴上有明显的Lead free 标识Lead Free identification/symbol in JABIL (JABIL 所采用的无铅识别标志)WI/ VA / PCP and process flow chart(WI/VA/PCP 及制程图表等文件用的无铅标识: )Lead Free identification/symbol in JABIL(JABIL 所采用的无铅识别标志)LF sticker/logo to display and show LF indirect material usage and rework tools: (无铅辅料, 维修工具等用的无铅标识:)Lead Free identification/symbol in JABIL(JABIL 所采用的无铅识别标志)LF logo paper to display on LF Bay area / machine equipment: (无铅生产线, 区域, 机器设备用的无铅标识☺PCB Assembly process requirementPCB 组装生产制程方面的要求Clear identification label/marking for Lead Free Component (清楚明晰的无铅元件标识)Clear identification label/marking for Lead Free process(清楚明晰的无铅生产制程标识)Clear identification label/marking for Lead Free Tooling(清楚明晰的无铅生产工具标识)Operator must have the Operating certification Card.(作业人员必须有上岗操作证)All Production operation must have WI (working instruction) support.(所有的生产运行作业必须有工作指支持)Summary of Lead Free (无铅化要点小结)Assembly/material doesn’t have Lead (Pb) substance, or Pb is Less than 0.1% weight of a products.(产品/物料不含铅,或含铅量小于产品/物料重量的0.1%.)It must have the capability to withstand the high soldering temperature condition, if the Lead Free material need to go through high temperature soldering process.(对于需经高温焊接的无铅物料,该物料必须能承受无铅焊接的高温环境条件)It should build a complete operation system to identify and trace the Lead free process, material, tools, equipments and assembly etc.(必须建立完善的无铅标识系统来区分,识别, 追踪无铅生产过程, 所用设备, 工具, 物料及最终的产品)All employees related to Lead Free project must pass the Lead free training.(所有涉及无铅项目的人员应该经过相关的无铅(Lead Free)知识培训)。
RoHS零件可焊性耐焊接热标准
RoHS s i/SO D R I I SO D R HE RE S IST N CE S R RoHS CO M PO N NDIP s, Wave Solder n DD IP Component, Wave Solder )i W: ±: ·265 –5/+0 ¢ 2.5¡0.5 secSolderability : Test Condition : TEMP. 265 –5/+0 ¢Time. 2.5¡0.5 secP: n90% H Wu dg m ent:90% coverage,[ RDS-02]Please see attachment for details[ RDS-02]: : 270 –0/+2 10¡0.5 sec [ºl]Resistance to Soldering Heat: Test Condition : TEMP. 270 –0/+2 ¢Time. 10¡0.5 sec (Terminal): 270 –0/+2 20¡0.5 sec [¥]Resistance to Soldering Heat: Test Condition : TEMP. 270 –0/+2 Time. 20¡0.5 sec (Body)P w: S S W w n Du dg m ent: Meet e orig i nal M ech a nical and E l ect r ical SPE C.[ RDS-02]Please see attachment for details[ RDS-02]SMD s, Solder Reflow n DS MT Component, Solder reflow)i W: ±: 255 –5/+0 2.5¡0.5 secSolderability : Test Condition : TEMP. 255 –5/+0 Time. 2.5¡0.5 secP w: n90% H Wu dg m ent:90% coverage,[ RDS-02]Please see attachment for details [ RDS-02]: ±: ·265 –0/+5 ¢10 –0/+5 secResistance to Soldering Heat: Test Condition : TEMP. 265 –0/+5 Time. 10–0/+5 sec (Terminal)P: S S W w n Du dg m ent: Meet e orig i nal M ech a nical and E l ect r ical SPE C.[ RDS-02]Please see attachment for details[ RDS-02]c m ent:RDS-02 SOLDERABILITY & SOLDER HEAT RESISTANCE TEST FOR RoHS COMPONENT¦¹¥÷³W®æ¯Ç¤J¦U RoHS si s SPE C will b e included in NE W A P PRO SHEW___________________Supplier Named H_______________________Signature_________________________Company SealSolderability & Solder HeatResistance test for RoHScomponentRDS-02 B Page2 Revision HistoryNo. Description of Revision Rev. Approved Date1 Update Item 4.1.1,4.1.2 time of immerse flux and testingsolder temperature; update Item4.2.1,4.2.2 pre-heating time and temperature;add remark about Item4.3,4.4B.002345678910Top Victory Electronics(Fujian) Co., LtdDocument No. Rev. TTL Pages: 9 Solderability & Solder HeatResistance test for RoHScomponent RDS-02 B.00 Page31. PurposeThe purpose of this standard is to standardize solder ability & solder heat resistance test methods for RoHS component, thus to realize maintenance and improvement of their quality and reliability.2. ScopeThis standard applies to test methods for solder ability & solder heat resistance RoHS component to be used in TPV products.3. Solder ability & solder heat resistance test method for TPV RoHS component3.1 Solder ability test for RoHS component ------------------------------------------------------ P43.1.1 The standard of solder ability for lead-free wave flow solder component ---------------------P43.1.2 The standard of solder ability for lead-free reflow solder component--------------------------- P43.2 Solder heat resistance test for RoHS component ----------------------------------------- P53.2.1 The standard of solder heat resistance for lead-free wave flow solder component -------- P53.2.2 The standard of solder heat resistance for lead-free reflow solder component ------------- P63.3 The process parameter of TPV lead-free reflow solder --------------------------------- P73.4 The process parameter of TPV lead-free wave flow solder ---------------------------- P83.5 The physical characteristic of TPV lead-free solder --------------------------------------- P9Top Victory ElectronicsDocument No. Rev. TTL Pages: 9 (Fujian) Co., LtdSolderability & Solder HeatResistance test for RoHScomponent RDS-02 B.00 Page44.1 Solder ability test for RoHS component4.1.1 The standard of solder ability for lead-free wave flow solder component:Samples size: 5pcsPre-process: The samples’ terminals should be immersed in the flux(recommend use: Vital GW9810A-6A, YONO-6810) for 2±0.5seconds, the immersion depth of terminals below their body of 1.5 ~2.0mm.Test method: After that, the terminals should be immersed in the solder bath setat 265 -5/+0¢J, for a duration of 2.5±0.5 seconds. Then, move themout of solder bath.Judgement: Inspect all immersed terminals, if the wetted area is uniform andsmooth, and newly wetted area compare immersed area is morethan 90%; Now we can judge component’ solder ability is OK.4.1.2 The standard of solder ability for lead-free reflow solder component:Samples size: 5pcsPre-process: The samples’ terminals should be immersed in the flux(recommend use:Vital GW9810A-6A, YONO-6810) for 2±0.5seconds,Test method: After that, the terminals should be immersed in the solder bath setat 255 -5/+0¢J, for a duration of 2.5±0.5 seconds. At last, move themout of solder bath.Judgement: Inspect all immersed terminals; if the wetted area is uniform andsmooth, and newly wetted area compare immersed area is morethan 90%; Now we can judge component’ solder ability is OK.NOTE：1. The sample is indivisibility (e.g. chip inductance, chip resistor, chip ceramic capacitor). So we must immerse the whole sample in the solder bath to test thesolder ability of terminal. (chip electronic capacitor exempted )2. If the sample body size is bigger or terminal length is longer than otherscomponent (e.g. Chip transformer); we can cut off the terminal from the body totest the solder ability.3. Composition of solder: 96.5%Sn+3.0%Ag+0.5%CuTop Victory ElectronicsDocument No. Rev. TTL Pages: 9 (Fujian) Co., Ltd4.2 Solder heat resistance for RoHS component4.2.1 The standard of solder heat resistance for lead-free wave flow solder componentSamples size:10pcsTest step: Put the specimens’ body that distance from the solder surface 3 ~5mm,and the solder temperature is 270+2/-0¢J. The samples must be cover bya box. We used a thermometer to measure the temperature that distancefrom the top of samples 2~3mm, the temperature must achieve 120±2¢Jfor120±2 seconds; After per-heating, immediately immerse the specimenin the bath set at 270+2/-0¢J from the terminal to the body 1.5~2.0mm, fora duration of 10±0.5 seconds.Judgement:Machine characteristic: After testing the samples, inspect the surface of samplesand joint of pin with a 40X or more microscope, phenomena ofcrack is not allowed; the intensity of terminal must meet tospecification; and plastic parts should show no any break,distortion, change colours, fragile etc. The paint of PCB orothers component have no change of colours, brush off, burnetc.Electric characteristic: The electric parameter must meet the specification.NOTE: If the inside temperature doesn’t achieve the required temperature, we can add a heater to achieve the require temperature.Top Victory ElectronicsDocument No. Rev. TTL Pages: 9 (Fujian) Co., Ltd4.2.2 The standard of solder heat resistance for lead-free reflow solder componentSamples size:10pcsTest step: Put the specimens’ body that distance from the solder surface 3 ~5mm,and the solder temperature is 265+5/-0¢J. The samples must be cover bya box. We used a thermometer to measure the temperature that distancefrom the top of samples 2~3mm, the temperature must achieve 180±5¢Jfor120±2 seconds; After per-heating, immediately immerse thespecimen terminal (distance between to the body 1.5~2.0mm) orspecimen itself in the bath set at 265+5/-0¢J for a duration of 10±0.5seconds. Then remove samples out from the solder bath, in the roomtemperature 2 hours for cooling; pre-heating, soldering, coolingprocess as a whole cycle. 3 cycles for each sample.Judgement:Machine characteristic: After testing the samples, inspect the surface of samplesand joint of pin with a 40X or more microscope, phenomena ofcrack is not allowed; the intensity of terminal must meet tospecification; and plastic parts should show no any break,distortion, change colours, fragile etc. The paint of PCB orothers component have no change of colours, brush off, burnetc.Electric characteristic: The electric parameter must meet the specification..NOTE: If the inside temperature doesn’t achieve the required temperature, we can adda heater to achieve the require temperature.Top Victory ElectronicsDocument No. Rev. TTL Pages: 9 (Fujian) Co., Ltd4.3 The process parameter of TPV lead-free reflow solderNotice：1. The speed from normal temperature to 150¢J is 1 ~ 4¢J/sec；2. Pre-heating temperature is 150 ~ 180¢J, for a duration about 60 ~ 90 seconds;J30 seconds; if the peak temperature is3. Temperature 220, for a duration about235¢J, the duration for 8 ~12 seconds; if the peak temperature is 250¢J, the durationfor 2 ~3 seconds;J;4. The speed of refrigerate is 2 ~10/sec5. The total time of reflow solder is about 6 minutes.Note: The temperature curve of lead-free reflow solder which supplier provide must meet TPV requirement. The supplier’s every temperature of curve must higher 10¢J than TPVrecommend the temperature curve. The duration must longer 20~30% than TPVrecommend. The exterior of samples not allowed have any damnification or distortion.The electric parameter must meet specification definition.Top Victory ElectronicsDocument No. Rev. TTL Pages: 9 (Fujian) Co., LtdSolderability & Solder HeatResistance test for RoHScomponent RDS-02 B.00 Page84.4 The process parameter of TPV lead-free wave flow solderNotice:1. Pre-heating temperature is 100 ~ 120¢J, for a duration about 86 ~ 100 seconds, thespeed of raise temperature is 1 ~2¢J/sec.2. The peak temperature is 250~258¢J, the duration for 3~4 seconds.3. The speed of refrigerate is 1 ~3/secJ;4. The total time of reflow solder is about 3.5 minutes.Note: The temperature curve of lead-free wave flow solder which supplier provide must meet TPV requirement. The supplier’s every temperature of curve must higher 10¢J than TPV recommend the temperature curve. The duration must longer 20~30% than TPVrecommend. The exterior of samples not allowed have any damnification or distortion.The electric parameter must meet specification definition.Top Victory Electronics (Fujian) Co., LtdDocument No. Rev. TTL Pages: 9Solderability & Solder Heat Resistance test for RoHScomponentRDS-02 B.00 Page 94.5 The physical characteristic of TPV lead-free solder4.5.1 Composition of lead-free solderSpecification: 96.5Sn 3.0Ag 0.5CuSubstance Sn Ag Cu Sb Bi Zn Fe Al As Cd Pb Content% rest Lessthan0.1%0.5±0.05%Less than 0.12%Less than 0.1%Less than 0.002%Less than 0.02%Less than 0.002%Less than 0.03%Less than 0.002%Less than 0.1%4.5.2 Solder bar of lead-free specLiquidus temperature (¢J ) 221 Solid status temperature （） 216 Lognitudinal strength （kgf/mm 2） 3.7Ductile 334.5.3 Physical characteristic about solder paste of lead-freeItem Characteristic Method of testWater solution resistance(Ω.m)More than 1×103 JIS Z 3197 8.1.1(1999) Flux content (wt%） 10.5±0.03JIS Z 3197 8.1.2(1999) Chlorine content （wt%） 0.07±0.02JIS Z 3197 8.14.2.1(1999) Copper plate corrosion qualified JIS Z 3197 8.1.4.2.3(1999)GQ GKGrain size （um ） Sphere10-38Sphere20-45JIS Z 3284 Annex1 Melting temperature （）216-221 DSC Flux fluorine test No fluorine JIS Z 3284 Annex 240¢J 90% More than 1×1012Insulationresistance Ω 85¢J 85% More than 5×108 JIS Z 3284 Annex 3Flux residue corrosion test No corrosion JIS Z 3284 Annex 4GQ GKPrintability 0.4mmpitch0.5mm pitchJIS Z 3284 Annex 5 Viscosity (Pa.s) 180±20 JIS Z 3284 Annex 6 Printing sinking test Without in series of 0.2mmJIS Z 3284 Annex 7Heating sinking test Without in series of 0.2mmJIS Z 3284 Annex 8Initial stage More than1.0Nadhesive 24 hours late More than1.0NJIS Z 3284 Annex 9wetting effective Level 2 (Copper plate) JIS Z 3284 Annex 10 Initial stage Level 1-3Solder ball test 24 hours late Level 1-3JIS Z 3284 Annex 11Reflow residue adhesiveness Not adhesive JIS Z 3284 Annex 12Migration test No occur JIS Z 3284 Annex 13。
Reflow曲线测试
40 sec
60 sec
80 sec Soaking Time由40~120皆有良好的焊 接情形
100 sec
120 sec
5ห้องสมุดไป่ตู้
Soaking temperature
測試150、170、190℃ 觀察焊接狀況
150℃
170℃
190℃
Soaking temperature 由150至190皆有良好焊接狀況
6
Reflow
測試斜率0.6、1.2、1.8、2.4、2.6 ℃/ sec 觀察焊接狀況
0.6
1.2
1.8 斜率0.6 ℃/ sec發生表面融錫稍差的情 況，提高至1.2 ℃/ sec以上後，焊接情 形良好
2.4
2.6
7
Peak Temperature
測試225、235、245、250℃ 觀察焊接狀況
pre-heat
50
soaking
100 150
reflow cooling
200 250 Sec.
T3 : time above 220 ℃ :
經測試後所模擬出的溫度曲線圖，在此範圍內，錫膏可得到良好的焊接效果 ramp up rate during reflow雖然可測試在2.6 ℃/ sec時焊接性良好，但考慮到零件 與PCB板的耐熱極限，故僅建議最大升溫斜率為2.3 ℃/ sec
10
溫度曲線圖
250
D ℃/sec
220 200
F~G ℃
A: ramp up rate during preheat : B~ C : soaking temperature: D: ramp up rate during reflow: E: ramp down rate during cooling: F~G : peak temperature:
如何高效的设定Reflow温度曲线,SMT,SMT技术文章-SMT 技术文章
比如，Paramax98的温区长度为98inch，曲线时间长度要求3.5min，那么
传输速度＝98inch×2.54/3.5≈71cm/min
在71cm/min的基础上通过修改其他参数，传输速度浮动±15cm/min都是可以接受的。传热率和加热效率越高，速度的调节窗口就越大。
传输速度
当回流焊炉确定以后，传输速度取决于曲线的形状要求、传热率以及产品和夹具的形状、材料和大小等。
一般情况下，产品和夹具的材料是不会变的，而复杂多变的是其形状和大小。对于不同的炉子，这里有一个简单的公式可以大概计算传输速度：
摘要：为了准确的设定温度曲线的每个参数，必须综合考虑影响温度曲线参数设置的各种因素，包括：PCB的内层结构、材料、密度，夹具类型，元器件类型，焊盘（镀层）和引线的材料，回流炉的性能（加热方式、加热效率，各温区的抗干扰性等），焊膏合金成分和Flux特性等。
关键字：回流焊，RTS，RSS，传热率
对于焊点的可靠性，用肉眼是很难判断的，有时你看到的焊点光亮有泽，但实际上它或许经历了过高的峰值温度或高温下停留过久，其焊点机械性、导电性和可靠性已经严重下降。当然回流不足也会导致同样的后果，同时会产生冷焊、虚焊或假焊等缺陷。
回流过程中形成的金属间化合物（IMC）的厚度对焊点可靠性影响最为显著。焊点连接不是简单的机械连接，而是一种冶金结合过程，它要通过熔化的合金在焊接界面上相互扩散形成IMC来保证连接的可靠性。
2、 缓解吸芯
RSS在回流区的温升斜率较高，而且没有在液相温度附近有一短暂的时间停留，很容易导致元器件的引线温度比焊盘温度高很多，使得Flux和锡膏大部分流到温度较高的引线上，最
后引起脱焊，这就是吸芯现象。RTS则巧妙的杜绝了这种现象。
隔夜焊口第二天的工艺流程
隔夜焊口第二天的工艺流程英文回答：The process of reflow soldering for overnight joints on the second day involves several steps to ensure the proper formation of the solder joint. Here is the typical workflow:1. Inspection: The first step is to inspect theovernight joints for any defects or issues. This includes checking for proper alignment, cleanliness, and any visible signs of damage. If any problems are found, they need to be addressed before proceeding to the next step.2. Preheating: After inspection, the overnight joints need to be preheated before reflow soldering. Preheating helps to remove any moisture or contaminants that may have accumulated overnight. This is typically done using a preheating oven or a hot plate.3. Flux application: Once the joints are preheated,flux is applied to the soldering area. Flux helps to remove oxides and other impurities from the surface of the joint, ensuring a clean soldering process. It also helps to improve wetting and solder flow.4. Reflow soldering: The preheated and fluxed joints are then subjected to reflow soldering. This involves heating the joints to a specific temperature where the solder paste melts and forms a bond between the components. The temperature and time profile for reflow soldering may vary depending on the specific solder paste and components being used.5. Cooling: After reflow soldering, the joints are allowed to cool down gradually. Rapid cooling can cause thermal stress and lead to solder joint defects. Cooling can be achieved by turning off the heat source or using a cooling fan.6. Inspection and testing: Once the joints have cooled down, they need to be inspected again to ensure the solder joints are formed correctly. This includes checking forproper wetting, fillet formation, and overall joint quality. Additionally, electrical testing may be performed to verify the integrity of the solder joints.7. Cleaning: If necessary, the soldered joints can be cleaned to remove any flux residue or other contaminants. This can be done using a cleaning solution or a specialized cleaning process.8. Final inspection: The last step is a finalinspection to ensure that all the joints meet the required quality standards. This includes checking for any defectsor issues that may have been missed during the previous inspections.中文回答：隔夜焊口第二天的工艺流程包括几个步骤，以确保焊接接头的正确形成。
- 1、下载文档前请自行甄别文档内容的完整性，平台不提供额外的编辑、内容补充、找答案等附加服务。
- 2、"仅部分预览"的文档,不可在线预览部分如存在完整性等问题,可反馈申请退款(可完整预览的文档不适用该条件!)。
- 3、如文档侵犯您的权益，请联系客服反馈,我们会尽快为您处理(人工客服工作时间：9:00-18:30)。
Several key areas of reflow soldering and temperature partitioning and types of reflow soldering.
A. The key areas affecting the furnace temperature are:
1. The temperature setting value of each temperature zone;
2. The temperature difference of each heating motor;
3. The speed of the chain and the mesh belt;
4. The composition of the solder paste;
5. The thickness of the PCB board and the size and density of the components;
6. The number of heating zones and the length of reflow soldering;
7. The effective length of the heating zone and the characteristics of the sputum;
B. Partition of reflow soldering:
1. Preheating zone (aka: warming zone);
2. Constant temperature zone (heat preservation zone / active zone);
3. Recirculation zone;
4. Cooling zone;
How to set the data of the reflow soldering temperature curve:
1. Set according to the temperature profile using solder paste. Solder pastes with different metal contents have different temperature profiles. The reflow soldering temperature profile of the specific product should be set according to the temperature profile provided by the solder paste manufacturer;
2. According to the material, thickness, multi-layer board, size, etc. of the PCB;
3. Set according to the density of components mounted on the surface mount board, the size of components, and special components such as BGA and CSP;
4. According to the specific conditions of the equipment, such as: the length of the heating zone, the material of the heating source, the structure of the return (re)flow soldering furnace and the heat conduction mode;
Lead-free temperature analysis:
The melting point of lead-free solder paste is 217 degrees. The composition of common lead solder paste is: Sn/Ag/Gu. The ratio is: 96.5/3.0/0.5
First, the preheating zone
The preheating zone is heated to 175 degrees and the time is about 100S, so that the heating rate of the preheating zone can be obtained (since the tester is online test, it has not entered the preheating zone from 0 to 46S, time 146 -46=100S, since room temperature is 26 degrees 175-26=149 degrees heating rate; 149 degrees/100S=1.49 degrees/S);
Second, the constant temperature zone
The high temperature in the constant temperature zone is about 200 degrees, the time is 80S, and the difference between the high temperature and the low temperature is 25 degrees; Third, the recirculation zone
The high temperature in the recirculation zone is 245 degrees, the low temperature is 200 degrees, the time to reach the value is about 35/S; the heating rate in the recirculation zone is:
45 degrees / 35S = 1.3 degrees / S. (How to set the temperature correctly Curve) It can be seen that the temperature curve reaches the value for too long. The total return time is about 60S; Fourth, the area is
The time in the area is about 100S, the temperature is reduced from 245 degrees to 45 degrees, and the speed of the 泠is: 245 degrees - 45 degrees = 200 degrees / 100S = 2 degrees / S.。