钛合金加工过程中晶粒尺寸的模拟与分析
2018-06-20
作者：钟鑫，赵军，王银涛，庞记明
单位：山东大学
摘要：基于晶体重结晶理论对TC4加工过程中晶粒细化进行模拟和分析。利用ABAQUS建立了TC4正交切削有限元模型，并通过正交切削试验获得的切削形态和切削力对仿真模型的可靠性进行了验证。利用JMAK模型，借助Fortran语言和Microsoft Visual编程环境编写晶粒细化子程序(Vumat)。通过ABAQUS提供的用户子程序接口，将程序嵌入到正交切削模型中对TC4加工过程中晶粒细化进行了模拟。结果表明：切屑晶粒细化主要发生在剪切区和第二变形区，剪切区晶粒细化程度大于第二变形区；已加工表面晶粒细化层深度小于塑性变形层深度和温度影响层深度；塑性变形和切削温度对晶粒细化均有影响，塑性变形对晶粒细化起主要作用。
关键词：晶粒细化；TC4钛合金；ABAQUS子程序；仿真；晶体塑性理论
中图分类号：TG506.7；TH161文献标志码：A
Simulation and Analysis of Grain Size in Machining Titanium Alloy
Zhong Xin，Zhao Jun，Wang Yintao，Pang Jiming
Abstract:Based on the theory of recrystallization，the grain refining of TC4 is simulated and analyzed.The TC4 orthogonal cutting finite element model is established by ABAQUS，and the reliability of the simulation model is verified by the chip shape and cutting force obtained in the orthogonal cutting experiment.Based on the JMAK model，the grain refinement subroutine (Vumat) is prepared with Fortran language and Microsoft Visual programming environment.Through the user subroutine interface provided by ABAQUS，the program is embedded into the orthogonal cutting model to simulate the grain refining in machining TC4.The results show that the grain refinement of the chip occurs mainly in shear zone and second deformation zone，and the degree of shear zone refinement is greater than that in the second deformation zone.The grain refinement layer depth of the machined surface is less than the plastic deformation depth and temperature affected depth.Both plastic deformation and cutting temperature have influences on grain refinement，but plastic deformation plays a dominant role in grain refinement.
Keywords:grain refinement；TC4 titanium alloy；ABAQUS subroutine；simulation；crystal plasticity theory