脉冲电流对Ti-6Al-4V合金显微组织及力学性能的影响  

Effect of pulse current on microstructures and mechanical properties of Ti-6Al-4V alloy

作　　者：林化强[1] 赵洋[2] 李丁园[2] 李光玉[1] 

机构地区：[1]吉林大学汽车材料教育部重点实验室,长春130022 [2]吉林大学通信工程学院,长春130022

出　　处：《吉林大学学报（工学版）》2008年第5期1060-1064,共5页Journal of Jilin University:Engineering and Technology Edition

基　　金：高等学校博士学科点专项科研基金项目(20050183053)

摘　　要：采用组织观察、性能检测、断口分析等方法研究了脉冲电流对Ti-6Al-4V合金显微组织及力学性能的影响。结果表明,脉冲电流使试样瞬间急速升温、产生较高的热压应力,并发生α→β相变,随后试样快速降温冷却发生β→α′相变。由于急速升温和快速冷却,新相的形核率增加且无充足时间长大,使合金的显微组织细化,而相变和组织细化导致了合金力学性能提高和电阻率变化。适当优化电脉冲处理工艺参数可使Ti-6Al-4V合金的综合力学性能明显提高。通过测量电阻变化可间接表征电脉冲处理后材料微观组织结构的变化程度。The effects of the pulse current on the microstructures and mechanical properties of Ti 6A1- 4V alloy were investigated using microstructures observation, mechanical testing and fracture analysis. The results show that pulse current causes the rapid increase in temperature of specimen, formation of comparatively high thermal compressive stress, phase transition from a to β. Subsequently, β is transformed into α＇ due to higher cooling speed. As a result of highrheating and cooling rates, for the new phase, the nucleation rate increases but the growth time decreases, resulting in the refinement of the microstructure. The combination of phase transition and microstructural refinement gives rise to the improvement in mechanical properties and change in resistance of Ti-6A1 4V alloy. Mechanical properties of Ti-6A1-4V alloy can be enhanced remarkably by optimizing electropulsing parameters. Transformation degree of the microstructure canbe characterized indirectly after electropulsing treatment by measuring the change in resistance.

关 键 词：材料合成与加工工艺 脉冲电流 Ti-6A1—4V合金 显微组织 力学性能 

分 类 号：TG156[金属学及工艺—热处理]