电脉冲时效对Fe14Mn6Si8Cr5Ni合金微观组织及形状记忆效应的影响  

Effect of electropulsing ageing on microstructure and shape memory effect in Fe14Mn6Si8Cr5Ni alloy

作　　者：杨世洲[1,2] 李宁[1] 文玉华[1] 彭华备[1] 刘文博[1] 

机构地区：[1]四川大学制造科学与工程学院,四川成都610065 [2]西华大学材料科学与工程学院,四川成都610039

出　　处：《功能材料》2012年第3期401-404,共4页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(50871072)

摘　　要：研究了电脉冲时效对Fe14Mn6Si8Cr5Ni合金微观组织及形状记忆效应的影响。研究结果表明预变形后的合金经电脉冲时效其形状记忆效应提高幅度比不预变形合金电脉冲时效幅度大。10%拉伸预变形合金经电脉冲时效1s,其形状回复率便提高到(70.3±1.0)%;时效300s,其形状回复率提高到(87.5±1.0)%,比固溶态合金提高了82.3%,而不预变形直接电脉冲时效合金只比固溶态合金提高了22.3%。经金相和TEM分析,预变形后电脉冲时效的合金中已无热诱发ε马氏体出现,这使得基体奥氏体增多;同时电脉冲能促使预变形时引入的空位和位错迅速崩塌形成层错。正是这两方面的原因使得预变形后电脉冲时效能迅速地提高合金的形状记忆效应。The effects of electropulsing ageing on microstructure and shape memory effect in Fe14Mn6Si8Cr5Ni alloy have been studied.The results show that electropulsing ageing after pre deformation has a much more remarkable improvement in shape memory effect than directly electropulsing after water quenching.The shape recovery ration in Fe14Mn6Si8Cr5Ni alloy can rise up to（70.3±1.0）% through electropulsing ageing for 1s,up to（87.5±1.0）% for 300s after 10% tensile pre deformation.The shape recovery ration of 87.5% is increased by 82.3% compared to that in a water-quenching alloy,while it can be only increased by 22.3% through directly electropulsing ageing.Metallographic and TEM analysis show that no thermal induced ε martensite in an alloy electropulsing aged after pre deformation appears and it results in increase of the austenite matrix.What is more,electropulse can accelerate collapsing of vacancies and dislocations introduced by pre deformation and the formation of stacking faults.It was the above two reasons that make the rapid improvement in shape memory effect through electropulsing ageing after pre deformation.

关 键 词：电脉冲时效 FE-MN-SI-CR-NI合金 形状回复率 相变点 预变形 

分 类 号：TG139.6[一般工业技术—材料科学与工程] TG156.92[金属学及工艺—合金]