面向认知公差的精密冲压工艺适应性设计方法（英文）

An adaptive design method for understanding tolerance in the precision stamping process

目的:精密冲压工艺过程中环境变量的波动导致工件出现破裂和皱褶等缺陷。探讨精密冲压工艺过程中环境变量(工件材质、冲压速度、压力、模具间隙和温度变化等)对冲压质量的影响,研究适应性工艺设计方法,提高精密冲压工件的质量。创新点:1.通过马尔科夫模型方程,推导出环境变量与精密加工波动公差之间的关系;2.建立试验模型,成功模拟适应性冲压工艺过程。方法:1.通过实验分析,推导出冲压过程中的晶粒流动和强度变化对成型零件的尺寸公差波动产生较大的影响(图2和3);2.通过理论推导,构建环境变量与加工波动公差之间的关系,得到适应性的工艺参数调节方案(公式16);3.通过仿真模拟,运用适应性设计方法在精密冲压过程中对工艺参数进行适应性调节,验证所提方法的可行性和有效性(图5)。结论:1.精密冲压过程中工艺参数需要根据不同的环境变量进行调节;2.环境变量与加工波动公差之间存在映射关系,运用隐马尔科夫模型实现关联表征;3.运用适应性设计方法对精密冲压工艺参数进行调节,加工波动公差明显减小,工件质量得到提高。

With the development of precision manufacturing, the understanding of tolerance has become a research hotspot in the field of manufacturing. An adaptable design method for understanding tolerance in the precision stamping process is proposed in this study. First, fluctuations of tolerance which are caused by differences in the stamping process are analyzed, such as differences in material and thickness, which can lead to changes in the metal flow stress curve. Second, a condition-driven adaptive design method is constructed based on a monitoring system and hydraulic control system. The mapping rules between multiple dis- turbance factors and the execution strategy are established by the hidden Markov model algorithm. Third, executive parameters, such as velocity, pressure, and gaps, are calculated and optimized by the data statistics of partial tolerance fluctuations in the control module. Then disturbances of various conditions could be adaptively controlled timely and effectively by the executive parameters. Finally, the adaptive design method for tolerance of one precision stamping part is applied, and the effect of the application is proved by the optimized results.