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本文综合了近年来国内外发表的有关马氏体形态的文献,介绍了钢中马氏体的分类、阐述了板条马氏体的两种立体形态及马氏体束内板条相对位向的n次回转关系。分析了影响钢中马氏体形态的各种因素。同时阐述了新近提出来的一些概念,诸如,随着冷速的增加,Ms点跳跃式的下降,并形成两个水平阶——等温阶及变温阶,二者均随含碳量的增加而下降,并呈直线关系,但斜率不同,对于Fe-C合金,在0.6%C处相交;含碳量低于0.6%时,先形成板条马氏体,高于0.6%时,则先形成片状马氏体;随着合金元素含量的增加,奥氏体层错能先降后增;奥氏体的屈服强度及层错能是影响马氏体形态的最基本的决定性的因素,等等。马氏体及其形态控制因素方面的研究是热处理基础理论的重要部分。这方面的研究工作,近年来有了飞跃的进展。自1976年以来,先后召开了三次马氏体相变国际会议,成立了马氏体国际委员会[1,2,3]。几年来,在马氏体形态及其影响因素方面发表了很多文章。然而,在国内,正式总结和评述这些成果的文章却很少。徐祖耀[4]、司鹏程[5]等曾综述了1977年以前的情况。本文着重从近几年来的国内外资料中评述钢中马氏体的分类、马氏体形态及其控制因素方面的新见解。
In this paper, the literature about martensitic morphology published in recent years is summarized, the classification of martensite in steel is introduced, and the two kinds of three-dimensional morphology of lath martensite and the relative orientation of lath in martensite beam N times the rotation relationship. The factors affecting the martensite morphology in steel were analyzed. At the same time, some newly proposed concepts are described, such as Ms decreasing abruptly with the increase of cooling rate and forming two horizontal steps - isothermal step and variable temperature step, both of which increase with the increase of carbon content But the slope is different. For Fe-C alloy, it intersects at 0.6% C; when the carbon content is less than 0.6%, lath martensite is formed first, and when it is higher than 0.6%, it forms first As the content of alloying elements increases, the fault of austenite layer firstly decreases and then increases. The yield strength and stacking fault energy of austenite are the most basic and decisive factors that affect the martensite morphology. Wait. The study of martensite and its morphology control factors is an important part of the basic theory of heat treatment. Research work in this area has made leaps and bounds in recent years. Since 1976, three international conferences on martensitic transformation have been held and the International Commission on Martensite has been established [1,2,3]. In recent years, many articles have been published on martensitic morphology and its influencing factors. However, there are very few articles in the country that formally summarize and comment on these achievements. Xu Zuyao [4], Si Pengcheng [5], etc. have reviewed the situation before 1977. This article focuses on reviewing martensite classification, martensite morphology and controlling factors in steel from domestic and foreign sources in recent years.