检测技术在自动化机械制造系统中的应用研究

检测技术在自动化机械制造系统中的应用,就是利用科学的、物理化学效应中各种能够对产品相关信息进行检查、验证、测量,并给予定性、判断的技术手段,它的最终定量对产品质量的好坏、产品的精密度有着重要的指导作用和影响,从而影响企业的长远发展。     

宏微观耦合本构模型参数识别取值范围研究

宏微观耦合本构模型的参数识别往往通过反分析方法进行,为了使参数识别结果具有高的置信度,需要确定合适的参数取值范围. 基于动态再结晶过程的微观机理以及相应本构方程的数学特征,提出一个确定参数取值范围的方法. 首先详细给出考虑动态再结晶的黏塑性本构模型,并根据模型构造物理机理,提出通过6 步确定该模型参数取值范围的方法;其次,对300M 低合金钢进行不同温度、应变速率下的热变形试验,测试宏观的流动应力-应变数据及微观的组织数据;然后应用提出的方法,依据试验数据,确定参数取值范围;最后,基于确定参数取值范围中获得的知识,对模型进行局部修改,使模型模拟结果更接近实验结果.      

Some improvements in visco-plastic model considering dynamic recrystallization

Some improvements in Jin‘s thermal visco-plastic constitutive model considering dynamic recrysytallization is presented in this paper. By introducing the influence of the strain rate on the mobility of dynamic recovery, the improved model can be more smoothly applied to numerical simulation of material flow behaviour and microstructure prediction during hot working. Another improvement is to consider the accumulated dislocation energy in the newly recrystallized grains as a resistance to the driving force of dynamic recrystallization volume. This improvement makes the predicted results of dynamic recrystallization progress agree better with the actual physical process.Finally, some numerical examples are given to show the advantages of the improved model and the ability to predict the dynamic recrystallization.