Ti-6Al-4V合金等径转角挤压有限元分析  

Finite Element Simulation of Ti-6Al-4V Alloy during Equal Channel Angular Extrusion

作　　者：王伟之[1] 程先华[1] 

机构地区：[1]上海交通大学机械与动力工程学院,上海200240

出　　处：《上海交通大学学报》2009年第5期704-707,712,共5页Journal of Shanghai Jiaotong University

摘　　要：运用点迹跟踪法对Ti-6Al-4V合金进行600°C等温条件下的等径转角挤压有限元模拟,探讨其跟踪点的等效应力、等效应变及温度场,分析挤压速度和摩擦系数对挤压过程的影响.结果表明:试样越靠近模具内角点部位的应变率带越狭窄,变形时间越短,则应变率越高;靠近模具内角点或外弧线处的变形过程不稳定且出现振荡;在挤压过程中,因塑性变形热使得试样内部温度急剧升高,最高升幅达100°C以上,对挤压有利且至关重要;在挤压模具转角处,速度和摩擦热对试样的应力场和温度场的核心区域分布影响显著.Particle tracking method was given to analyze the equal channel angular extrusion （ECAE） process of Ti-6Al-4V alloy in isothermal condition at 600 ℃. The distributions of effective strain, effective stress, and the temperature of selected particle tracking points were analyzed, respectively. The influence of extrusion speed and friction coefficient was also discussed. The study shows that the strain rate belt will become narrower when the part of specimen is closer to the inner corner, and at the same time, the strain rate becomes higher, the deforming time in treated is shorter. The process of deformation in specimen close to the inner corner or outer arc is not steady but oscillated. In steady ECAE process, deformation heat leads to drastic increasing of the specimen temperature, the highest of which is 100℃. This is not only helpful but also critical for the success of extrusion. In addition, the distribution of core area of the ef- fective stress is different when the extrusion speed is changed significantly from low speed to high speed; distribution of effective stress and temperature is also affected by the friction heat with different friction coefficients.

关 键 词：Ti-6Al—4V合金 等径转角挤压 应力与应变特性 温度场 有限元分析 

分 类 号：TG371[金属学及工艺—金属压力加工]