预形变对Fe-Mn-Si合金γε相变的影响  

STUDY OF PRESTRAIN ON γε TRANSFORMATION OF Fe-Mn-Si ALLOYS

作　　者：覃作祥[1] 陆兴[1] 屠明超[1] 张彦生[1] 

机构地区：[1]大连铁道学院材料科学与工程系,大连116028

出　　处：《金属学报》2001年第2期127-134,共8页Acta Metallurgica Sinica

基　　金：国家自然科学基金资助项目 59601007

摘　　要：预形变强烈诱发Ｆｅ－Ｍｎ－Ｓｉ合金产生γ→ε马氏体相变.预形变量较小时，形变诱发产生的γ→ε马氏体具有择优取向，同一晶粒内的ε马氏体片大多数取向相同；随预形变量增大，ε马氏体大量增多，ε马氏体片之间呈现交叉；预形变量越大，交叉现象愈严重，形变诱发的ε马氏体片的相互交叉是产生加工硬化的重要原因之一．预形变对Ｆｅ－ Ｍｎ－Ｓｉ合金εγ相变过程的相变温度影响显著，随着预形变量的增大，合金的相交点Ｍｓ有不同程度升高，且含Ｓｉ量越多，升高幅度越大；Ａｓ和Ａｆ都明显升高，其升高幅度更为显著．The γε transformations and microstructures of four prestrained Fe-Mn-Si alloys have been systematically studied by means of microscopy and electrica1 resistivity analysis. The results indicate that the pre-existed ε martensite and the strain-induced ε martensite strengthen workhardening behavior, the intersection mode of ε martensite plates is one of the important reason that causes work-hardening, and Si the raises the yield strength of Fe-32Mn alloy. It was found that the Si lowers the Neel temperature (TN) of austenite, reduces the stabilization of the austenite and promotes the strain-reduced γ→ε transformation. When the elongation is small, most of the strain-reduced ε martensite in a grain arrange in the same direction. e martensite plates are intersected with increasing tensile deformation. The effect of deformation on Fe-Mn-Si alloy is remarkable and the volume fraction of strain-reduced ε martensite increases with increasing elongation. The temperature Ms, As and Af increase obviously with increasing elongation.

关 键 词：FE-MN-SI形状记忆合金 γ=ε相变 拉伸形变 Ε马氏体 

分 类 号：TG139.6[一般工业技术—材料科学与工程] TG156.93[金属学及工艺—合金]