Modeling of material deformation behavior in micro-forming under consideration of individual grain heterogeneity  

考虑个体晶粒异质性的微成形材料行为建模

作　　者：Zhen-wu MA Xuan PENG Chun-ju WANG Zi-yang CAO 马振武;彭漩;王春举;曹自洋(苏州科技大学机械工程学院,苏州215009;苏州大学机电工程学院机器人与微系统研究中心,苏州215131)

机构地区：[1]College of Mechanical Engineering,Suzhou University of Science and Technology,Suzhou 215009,China [2]Robotics and Microsystems Center,School of Mechanical and Electrical Engineering,Soochow University,Suzhou 215131,China

出　　处：《Transactions of Nonferrous Metals Society of China》2020年第11期2994-3005,共12页中国有色金属学报（英文版）

基　　金：Project(51905362)supported by the National Natural Science Foundation of China;Projects(19KJB460022,18KJB130006)supported by the Natural Science Foundation of Jiangsu Higher Education Institution,China。

摘　　要：This study aims to develop a model to characterize the inhomogeneous material deformation behavior in micro-forming.First,the influence of individual grain heterogeneity on the deformation behavior of CuZn20 foils was investigated via tensile and micro-hardness tests.The results showed that different from thick sheets,the hardening behavior of grains in the deformation area of thin foils is not uniform.The flow stress of thin foils actually only reflects the average hardening behavior of several easy-deformation-grains,which is the reason that thinner foils own smaller flow stress.Then,a composite modeling method under consideration of individual grain heterogeneity was developed,where the effects of grain orientation and shape are quantitatively represented by the method of flow stress classification and Voronoi tessellation,respectively.This model provides an accurate and effective method to analyze the influence of individual grain heterogeneity on the deformation behavior of the micro-sized material.以个体晶粒异质性影响为基础建立能够描述微成形中材料变形行为不均匀特性的模型。首先,通过拉伸和显微硬度实验研究个体晶粒异质性对CuZn20箔材变形行为的影响规律。结果显示,与厚板不同,箔材变形区域中的晶粒硬化行为具有不均匀性。箔材的流动应力实际上只反映变形区域中易变形晶粒的平均硬化行为,这是箔材流动应力减小的原因。在此基础上,考虑个体晶粒异质性影响提出一种复合建模方法。分别使用流动应力分类方法和Voronoi剖分法对个体晶粒取向和形状的影响进行表征。该模型为分析个体晶粒异质性对微尺度材料变形行为的影响提供一种准确有效的方法。

关 键 词：MICRO-FORMING size effects inhomogeneous material behavior grain heterogeneity composite modeling 

分 类 号：TG115[金属学及工艺—物理冶金]