高碳钢中马氏体形貌及其结构(英文)  

Apparent morphology and structure of martensite in ultrahigh carbon steel

作　　者：张占领[1,2] 柳永宁[3] 张柯柯[1,2] 孙俊杰[1] 夏琦[1] 高莉华[1] 

机构地区：[1]河南科技大学材料科学与工程学院,河南洛阳471003 [2]河南省有色金属材料科学与加工技术重点实验室,河南洛阳471003 [3]西安交通大学金属材料强度国家重点实验室,陕西西安710049

出　　处：《材料热处理学报》2010年第9期33-36,共4页Transactions of Materials and Heat Treatment

基　　金：sponsored by the National Natural Science Foundation of China(NSFC)under grant No.50571077and50774029;the Science Fund for Distinguished Young Scholars of Henan Province,China,under grant No.074100510011

摘　　要：研究了含C量1.6%超高碳钢不同淬火条件下马氏体的形貌及其亚结构。结果表明,超高碳钢淬火组织随奥氏体化温度变化而发生显著变化。奥氏体化温度较高时形成粗大孪晶马氏体;奥氏体化温度较低时淬火组织为位错亚结构的板条马氏体、枣核状马氏体和少量孪晶马氏体,以及未溶碳化物。高分辨电镜观察表明,三维形态像枣核状的马氏体的亚结构为高密度位错。这是由于奥氏体化时碳化物分解比铁素体向奥氏体转变慢;碳化物分解过程中在碳化物原位形成位错堆积;淬火时马氏体优先在位错堆积处形核,并以位错滑移机制长大、增厚,最终形成板条马氏体或枣核状马氏体。Research was done on morphology and structure of martensite developed in an ultrahigh carbon steel containing 1.6 wt% carbon.It is shown that significant changes in microstructure with the different austenitizing temperature occur for the quenched steel.Coarse twin martensite forms by austenitizing at high temperature.In contrast,the microstructure consisting of submicron lath,jujubestone like martensite and some fine twin martensite,as well as undissolved cementite is observed for the steel austenized at lower temperature.Three dimensional jujube-stone like martensite with the sub-structure of high density dislocations is confirmed by the observation of high resolution electron microscopy（HREM）.It is suggested that the dissolution of carbide particles lags behind the ferrite to austenite transformation when the steel is being austenitized.Dislocation pile-ups form at the original positions where carbide particles are dissolved.During quenching,martensite nucleates at dislocation pile-ups,and grows and thickens through the mechanism of dislocations moving,and finally the lath martensite and jujube-stone like martensite form.

关 键 词：超高碳钢 马氏体相变 高分辨电镜 位错 

分 类 号：TG142.31[一般工业技术—材料科学与工程]