Mn对中锰钢α-Fe/γ-Fe界面影响的第一性原理研究  

First-principles Study on Effect of Mn onα-Fe/γ-Fe Interface in Medium-manganese Steel

作　　者：陈万超 汪杨 杨晴 张恒华[1] 张梅[1] CHEN Wanchao;WANG Yang;YANG Qing;ZHANG Henghua;ZHANG Mei(School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China)

机构地区：[1]上海大学材料科学与工程学院,上海200444

出　　处：《上海金属》2021年第5期102-106,112,共6页Shanghai Metals

摘　　要：采用基于密度泛函理论的第一性原理方法,对Mn原子进入α-Fe/γ-Fe界面前后的分离功、界面能、电子结构和成键特征等特性进行了分析。结果表明:Mn原子在逆相变过程中倾向于置换奥氏体一侧铁原子,即倾向于向奥氏体扩散,从而使奥氏体的临界形核功减小,临界形核半径减小,形核数量增加,热稳定提高。另外,界面态密度和Milliken布居分析也解释了Mn增强α-Fe/γ-Fe界面稳定性的原因,为Mn促进奥氏体形核提供了理论依据。Separation work,interfacial energy,electronic structure and bonding characteristics of theα-Fe/γ-Fe interface with or without Mn atoms were analyzed by first-principles method based on density functional theory.The results showed that the Mn atom tended to displace the Fe atom on the side of austenite,that is,tended to diffuse in austenite during the reverse-phase transformation process,which led to a decrease in both the critical nucleation work and the critical nucleation radius,correspondingly,to an increase in both the number of nucleation and the thermal stability of austenite.In addition,the density of interfacial states and Milliken population analysis were used to explain the reason why the stability of theα-Fe/γ-Fe interface was enhance by Mn element,which provided a theoretical basis for Mn promoting the nucleation of austenite.

关 键 词：第一性原理计算 界面能 电子结构 态密度 布居分析 奥氏体形核 

分 类 号：TG142.1[一般工业技术—材料科学与工程]