TiN/γ-Fe interface orientation relationship and formation mechanism of TiN precipitates in Mn18Cr2 steel  

作　　者：Zheng-hui Wang Jing-pei Xie Qian Li Wen-yan Wang Ai-qin Wang Pei Liu 

机构地区：[1]School of Materials Science and Engineering,Zhengzhou University,Zhengzhou 450001,China [2]School of Materials Science and Engineering,Henan University of Science and Technology,Luoyang 471023,China [3]National Center of International Research for Micro-nano Molding Technology,Zhengzhou University,Zhengzhou 450001,China [4]Provincial and Ministerial Co-construction of Collaborative Innovation Center for Non-ferrous Metal New Materials and Advanced Processing Technology,Henan University of Science and Technology,Luoyang 471023,China

出　　处：《China Foundry》2021年第3期180-184,共5页中国铸造（英文版）

基　　金：the financial support from the National Natural Science Foundation of China(Grant No.U1604251);the Major Scientific and Technological Project of Luoyang,China(Grant No.2001017A)。

摘　　要：A Mn18Cr2 steel containing TiN precipitates was fabricated by vacuum induction melting.The morphology of TiN precipitates and the interface orientation relationship between TiN and γ-Fe were characterized by means of SEM,TEM and SAED,and the formation mechanism of TiN precipitates in Mn18Cr2 steel was clarified.Results show that the TiN precipitates are more likely to exhibit a cubic-shaped morphology and form both within the grain and at the grain boundary of γ-Fe.The interface orientation relationship between TiN and γ-Fe is determined as follows:(100)_(TiN)//■_(γ-Fe),■_(TiN)//■_(γ-Fe).Because of the smallest interfacialmisfit,the secondary close-packed lane {100} of TiN preferentially combines with the close-packed plane {111} of γ-Fe during the precipitation in order to minimize the interface energy.After nucleation,the TiN precipitates exhibit cubic appearance due to the fact that the TiN has a FCC structure with rock salt type structure.This study provides reference for the material design of the austenitic high-manganese steels with excellent yield strength.

关 键 词：Mn18Cr2 steel TiN precipitates interface orientation relationship interface misfit 

分 类 号：TG142.11[一般工业技术—材料科学与工程]