金属微塑性成形中的尺度效应及其数值模拟技术  

Size Effects in Metal Microforming Processes and Related Numerical Modeling Techniques

作　　者：李雷[1,2,3] 谢水生[1] 米绪军[1] 曹建国[3] 

机构地区：[1]北京有色金属研究总院,有色金属材料制备加工国家重点实验室,北京100088 [2]河南理工大学材料科学与工程学院,河南焦作454000 [3]海亮集团有限公司浙江海亮股份有限公司,浙江诸暨311814

出　　处：《科技导报》2008年第1期76-79,共4页Science & Technology Review

基　　金：国家自然科学基金项目(50674017);河南理工大学博士基金项目(648524);青年骨干教师基金项目(649027)

摘　　要：介绍了金属微塑性成形过程中的两类尺度效应,即"越小越弱"和"越小越强",探讨了产生不同尺度效应的原因;介绍了能够反映尺度效应的物理模型及相应的数值模拟技术,指出了各类模型和数值技术面临的困难,预测了该研究领域的发展方向。Size effects, in evidence in metal microforming processes, either in form of ＂smaller is weaker＂ or in form of ＂smaller is stronger＂ are studied in this paper. Research shows that the dislocations and grains orientation play important roles. The physical models, especially, the continuum mechanics models, for size effects are discussed, together with related numerical methods. The strain gradient plasticity can explain the phenomena of ＂smaller is stronger＂. The problems and difficulties of these physical models related with the present numerical techniques are pointed out. It is shown that the meshless methods or multi-wavelets methods are promising in resolving the numerical difficulties for the strain gradient theory.

关 键 词：微塑性成形 尺度效应 应变梯度塑性理论 位错 数值模拟 MEMS 

分 类 号：TG301[金属学及工艺—金属压力加工]