过共晶高铬白口铸铁碳化物生长机制及影响因素分析  

Study on Carbides Growth Mechanism and Influencing Factors of Hypereutectic High Chromium White Cast Irons

作　　者：马幼平[1] 赵峰[1] 潘景余[2] 刘玉高[1] 李俊[1] 李泽宇[1] 

机构地区：[1]西安建筑科技大学冶金工程学院,陕西西安710055 [2]西北工业大学社会科学系,陕西西安710072

出　　处：《热加工工艺》2007年第1期14-16,共3页Hot Working Technology

基　　金：陕西省自然科学基金资助项目(2004E111)

摘　　要：采用Mg基复合变质处理的方法,研究了过共晶高铬白口铸铁凝固过程中碳化物的生长机理及尺寸形态的变化特性。研究结果表明:在过共晶高铬白口铸铁结晶过程中,变质元素Mg不仅造成热力学过冷,而且Mg可能吸附于碳化物择优长大的晶面上,起到阻碍碳化物片状长大的作用,使碳化物趋于细小、孤立,且边部钝化,使冲击韧度显著提高。Carbides growth mechanism and their morphology characteristics during solidification were investigated.by using Mg-matrix compound modificator in hypereutectic high chromium white cast irons. The results show that the modificator Mg can cause thermodynamic undercooling, and it may absorb in the crystal faces of preferential growth of carbides, which can slow down carbides growing up on plate type and make them tend to be fine, isolated and passivated, and thus the impact toughness is improved greatly.

关 键 词：变质处理 碳化物 吸附效应 热力学过冷 

分 类 号：TG143.7[一般工业技术—材料科学与工程] TG252[金属学及工艺—金属材料]