Fe-30Mn-6Si-xN形状记忆合金层错能的热力学计算  

THERMODYNAMICAL CALCULATION OF THE STACKING FAULT ENERGY IN Fe-30Mn-6Si-xN SHAPE MEMORY ALLOYS

作　　者：万见峰[1] 陈世朴[1] 徐祖耀[1] 

机构地区：[1]上海交通大学材料科学与工程学院,上海200030

出　　处：《金属学报》2000年第7期679-683,共5页Acta Metallurgica Sinica

基　　金：美国Emerson公司合作项目;教育部博士点专项科研基金!97024835资助项目

摘　　要：利用包含置换原子和间隙原子的层错能势力学模型，计算了不同 Ｎ含量下 Ｆｅ－３０Ｍｎ－６３Ｓｉ－ｘＮ形状记忆合金的层错能计算结果表明， Ｎ对合金层错能的作用是先增加后降低（存在一个转折点 ｐ，对应 Ｎ含量（质量分数）为 ωｐ）：当少量的 Ｎ固溶在合金中（ωＮ＜ωｐ）时，由于Ｎ和近邻原子间的交互作用，合金的层错能有所增加；在Ｎ含量比较高时（ωＮ＞ωｐ），Ｎ在层错区的偏聚对层错能的降低起了重要作用．Ｎ在合金中不同的间隙占位，将直接影响ωｐ值：Ｎ位于八面体间隙位置时，ωｐ约为０．３５％；若Ｎ位于四面体间隙位置，ωｐ仅为０．１５％．The stacking fault energy (SFE) in Fe-30Mn-6Si-xN alloys with different nitrogen contemns has been calculated by using a thermodynamical model considering the existence of both substitutional and inierstitial alloying atoms. The results show that SFE in alloys with lower nitrogen concentration (ωN <ω p) increases mainly due to the interaction between nitrogen and the neighboring atoms, and decreases in alloys with higher nitrogen concentration (ωN >ωp) that may be predominately caused from the segregation of nitrogen at stacking faults. The difference of nitrogen-occupation will directly effect the critical value of nitrogen content, ωp, when ωN = ωp the alloy possesses the highest SFE. ωp=0.35%N as N exists at octahedral interstice while N occupies the tetrahedral interstice, ωp=0.15%N.

关 键 词：FE-MN-SI 基形状记忆合金 层错能 热力学 

分 类 号：TG139.6[一般工业技术—材料科学与工程]