基于微体积成形的成形机理及传统的表面层模型,将分析体分为内部多晶区域、表面层晶粒内部区域和表面层晶粒影响区域。参考Hall-Petch公式并引入尺度参数,对微镦粗试验数据进行回归分析,构建纯铜晶界影响区域材料的本构方程。分区域赋予分析体材料本构关系并进行离散化处理,对纯铜微镦粗过程进行数值模拟,分析结果体现了微成形的基本特征,由分析结果得到的微成形材料本构关系与试验结果基本一致,证明所构建的晶界影响区域的材料本构关系和数值模拟模型的可靠性。
Based on the mechanism of micro-bulk-forming and the traditional surface layer model,the object is divided into the inner polycrystalline region,the inner region of the grains in the surface layer and the region affected by the grain boundary in the surface layer.Depending on Hall-Petch formula and introducing scale parameters,the constitutive equation of the region affected by the grain boundary is established through regressing the experiment data of the copper micro-upsetting.The micro-forming process is simulated after regionalization and discretization of the object.The simulation results reflect the characteristics of micro-forming and are consistent with the experiment result,which certify the reliability of the constitutive equation and the simulation model.