基于伺服压力机冲压速度对板料成形性的影响

作者：喻建军 2013 年 4 月 20
目
录
第一章 绪论 ....................................................................................................... 1 1.1 引言 ....................................................................................................... 1 1.2 伺服压力机的工作特点 ......................................................................... 1 1.3 伺服压力机在冲压工艺中的应用 .......................................................... 2 1.3.1 伺服压力机在拉延成形工艺中的应用 ......................................... 2 1.3.2 伺服压力机在国内外的应用研究 ................................................. 3 1.4 动力显式有限元仿真技术的应用 .......................................................... 4 1.4.1 动力显式算法简介 ....................................................................... 4 1.4.2 动力显式有限元技术的应用现状 ................................................. 5 1.5 研究目的和内容 .................................................................................... 6 1.5.1 研究目的 ...................................................................................... 6 1.5.2 研究内容 ...................................................................................... 6 第二章 板料成形有限元仿真理论 ..................................................................... 8 2.1 弹塑性本构关系 .................................................................................... 8 2.2 屈服准则 ................................................................................................ 9 2.2.1 Barlat 屈服准则 ............................................................................. 9 2.2.2 Hill48 屈服准则 ........................................................................... 10 2.3 塑性硬化准则 ...................................................................................... 11 2.4 过应力本构模型 .................................................................................. 12 2.5 本章小结 .............................................................................................. 13 第三章 冲压速度对板料成形性的影响 ............................................................ 14 3.1 不同应变率下的单轴拉伸实验 ............................................................ 14 3.2 材料本构模型的建立 ........................................................................... 18 3.3 方盒形件成形过程分析 ....................................................................... 19 3.3.1 盒形件拉深成形的变形特点 ...................................................... 19 3.3.2 方盒形件有限元模型的建立 ...................................................... 19 3.3.3 模拟结果分析 ............................................................................. 20 3.3.3.1 不同质量放大系数的动内能比 ......................................... 20 3.3.3.2 不同冲压速度下的模拟结果分析 ..................................... 21 3.4 本章小结 .............................................................................................. 29 第四章 汽车尾门内板成形工艺分析 ................................................................ 31 4.1 汽车尾门内板的工艺分析 ................................................................... 31 4.2 汽车尾门内板的拉延成形工艺设计 .................................................... 31
in the change process of stamping speed. The simulation results show that the material replacement the last door panel forming process can be achieved through a change in velocity. Finally, according to the results of finite element analysis, the last door panel was production debugging by the servo press, the results of commissioning and simulation are basically the same and get the qualified DC53D_ZF parts. The results not only realize the image of replacing the materials but also can provide some theoretical guidance to the companies for improving the production efficiency. Keywords : Servo Press; Punch Speed; Strain Rate; Last Door Panel
以方盒形件为例建立有限元模型研究不同冲压速度时应力应变厚度及应变率等参数的变化规律得出了合理的冲压速度曲其次对汽车尾门内板进行工艺分析确定板料为dc54dzf时的工艺利用板料成形有限元分析软件对成形过程中可能出现的缺陷进行预测得到了合理的工艺参数及合格的制件
基于伺服压力机冲压速度对板料成形性的影响
2013 年 04 月
基于伺服压力机冲压速度对板料成形性的影响 摘要
伴随着汽车行业将发展重心向节能和环保 转移，要求汽车制造工艺及装备 向着智能化、柔性化方向发展，伺服压力机应运而生。伺服压力机 省去了传统 压力机上飞轮、离合器等耗能部件，并以交流伺服电机直接 作为压力机的动力 源，实现滑块运动特性可控， 满足了冲压加工柔性化、智能化的需求。 本文基于伺服压力机特性，研究冲压成形过程中，冲压速度的变化对板料 成形性的影响，并以汽车尾门内板为例，在伺服压力机上， 改变压力机行程曲 线，实现低质材料高用，在保证质量的同时 ，节约生产成本。 首先，以 DC53D_ZF 为研究对象，进行力学性能实验，拟合得到材料在不 同应变率下的本构方程；以方盒形件为例，建立有限元模型， 研究不同冲压速 度时应力、应变、厚度及应变率等参数的变化规律，得出了合理的冲压速度曲 线。 其次，对汽车尾门内板进行工艺分析，确定板料为 DC54D_ZF 时的工艺， 利用板料成形有限元分析软件对成形过程中 可能出现的缺陷进行预测，得到了 合理的工艺参数及合格的制件。在相同条件下，用 DC53D_ZF 替换 DC54D_ZF 材料，进行了等强度计算，并用数值模拟方法进行了分析 ，结果表明在原有设 备及工艺条件下，采用 DC53D_ZF 材料时零件无法成形。 再次，在方盒形件研究的基础上，改变汽车尾门内板冲压成形速度曲线， 分析不同冲压速度变化时，板料对应节点的应力 应变分布，模拟结果表明，可 以通过速度变化实现 DC53D_ZF 替换 DC54D_ZF 材料。 最后，根据有限元分析结果，在伺服压力机上对汽车尾门内板进行调试成 形，其结果与模拟结果吻合，得到了合格的 DC53D_ZF 的汽车尾门内板件，实 现了材料替换的设想，为降低成本提供了依据。 关键词：伺服压力机；冲压速度；汽车尾门内板 ；冲压成形
Study of Influence of Punch Srvo Press
ABSTRACT
Accompanied by the development of the automotive industry focus on energy saving and environmental protection, automobile manufacturing technology and equipment are required to develop in the direction of the intelligent and flexible, Servo press arises at the historic moment. The servo press get rid of energyconsuming components such as traditional presses flywheel and clutch , the AC servo motor was used as the power source of the press to achieve the slide motion characteristics controlled, stamping flexible, intelligent needs were met. In this paper, the effects of stamping speed changes on sheet metal formability was researched during the process of stamping based on the s ervo presses characteristics. Take the automobile tail door panel for example, by changing the curves based on the servo presses, high use of low-quality materials was achieved, quality assurance was realized, production costs was reduced at the same time. First of all, take DC53D_ZF as the research object, experiment of mechanical properties was conducted, fit the constitutive equation in different strain rates. Box-shaped parts, for example, the finite element models for box-shaped parts of different stamping speed are established. Via observing the variation regulation of the parameters such as node stress, strain, thickness and strain rate during spee d change process, reasonable punch velocity curve was obtained then. Secondly, the process of Last Door Panel analyzed to determine the process pa rameters in the raw material DC54D_ZF, and the finite element model is establishe d based on sheet metal forming finite element analysis software to predict the possi ble defects of the part forming process and obtain a reasonable process parameters and qualified parts. Under the same conditions, simulate and prediction the last do or panel of DC53D_ZF replacement DC54D_ZF is replaced by DC53D_ZF, the res ult is analyzed by numerical simulation method under circumstance of the constant strength calculation, the results shows that under the condition of existing equipm ent and technology, adopting DC53D_ZF feasibility of replacing the original mater ial was not optimistic. Thirdly, based on the box-shaped member, the press-forming speed curve was created, the corresponding nodes parameters such as stress and strain were analyzed