Effects of rare earth oxide on hardfacing metal microstructure of medium carbon steel and its refinement mechanism

作     者：郝飞飞 廖波 李达 刘利刚 淡婷 任学军 杨庆祥 

作者机构：State Key Laboratory of Metastable Materials Science and Technology College of Materials Science and Engineering Yanshan University School of Materials Science and Engineering Southwest Jiaotong University School of Engineering Liverpool John Moores University 

出 版 物：《Journal of Rare Earths》 (稀土学报（英文版）)

年 卷 期：2011年第29卷第6期

页      面：609-613页

核心收录：

学科分类：080503[工学-材料加工工程] 081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 0805[工学-材料科学与工程（可授工学、理学学位）] 0802[工学-机械工程] 0703[理学-化学] 070301[理学-无机化学] 080201[工学-机械制造及其自动化] 

基　　金：Project supported by One Hundred Excellent Talents of Hebei Province of China (SPRC021) Key Project of Science and Technology of Hebei Province (09215106D) 

主　　题：hard-face-welding metal rare earth oxide microstructure heterogeneous nuclei repair 

摘      要：The electrodes for hardfacing medium carbon steel with six additions of rare earth oxide were developed in this work. By means of optical microscopy and scanning electron microscopy, the microstructure, inclusion and the fractograph of the hardfacing metal were observed. Then, the effects of rare earth oxide on microstructure and inclusions in hardfacing metal were analyzed. The effectiveness of rare earth oxide as heterogeneous nuclei of δ-Fe was calculated with the misfit theory. The results showed that, the microstructure of hardfacing metal was composed of ferrite and small amount of pearlite. The microstructure was refined at first and then coarsened with the increase of rare earth oxide addition. The fractograph was changed from brittle to equiaxed dimples, then became quasi-cleavage and cleavage gradually. The calculated results showed that, the ferrite grain size could be refined because that LaAlO3 as heterogeneous nuclei of δ-Fe was moderately effective, and the ferrite grain size was coarsened because the misfits between Ce2O3 and δ-Fe, Ce2O2S and δ-Fe were increased with futher increase of rare earth oxide addition.