热处理工艺对过共晶高铬铸铁组织及性能影响研究  

Effect of Heat Treatment on Properties of Hypereutectic High Chromium Cast Iron

作　　者：张凯 张建平 张祯 钟宁 卢尚文 ZHANG Kai;ZHANG Jian-ping;ZHANG Zhen;ZHONG Ning;LU Shang-wen(Department of Automotive Engineering,Hunan Industry Polytechnic,Changsha 410036,Hunan,China;Sany Heavy Industry Co.,Ltd.,Changsha 410199,Hunan,China;Institute of Marine Materials Science and Engineering,Shanghai Maritime University,Shanghai 200135,China)

机构地区：[1]湖南工业职业技术学院汽车工程学院,湖南长沙410036 [2]三一重工股份有限公司,湖南长沙410199 [3]上海海事大学海洋科学与工程学院,上海200135

出　　处：《铸造》2022年第9期1133-1138,共6页Foundry

基　　金：湖南工业职业技术学院校级课题GYKYZ201903。

摘　　要：采用覆膜砂铸造构建了定向凝固环境,制备了定向凝固过共晶高铬铸铁。研究了淬、回火工艺对过共晶高铬铸铁组织、硬度、韧性和耐磨性的影响。结果表明:热处理过共晶高铬铸铁组织中碳化物为MC,基体主要为马氏体,含有少量残余奥氏体。初生碳化物截面为六边形,总碳化物含量随淬火温度变化无显著改变。1100℃淬火时,初生碳化物发生了部分溶解。450℃回火时,硬度达到最大值。冲击功随回火温度升高,先增加后降低,450℃以上回火,冲击功再次增加。980、1100℃淬火时,最佳耐磨性出现在350℃回火,而1050℃淬火时,最佳耐磨性出现在450℃回火。Directionally solidified hypereutectic high chromium cast iron was prepared by precoated sand casting. The effects of quenching and tempering process on the microstructure, hardness, toughness and wear resistance were studied. The results show that the carbides of heat treated hypereutectic high chromium cast iron are MC, the matrix is mainly martensite and contains a small amount of residual austenite. The section of primary carbide is hexagonal, and the total carbide content does not change with quenching temperature.When quenched at 1 100 ℃, the primary carbides were partially dissolved. When tempering at 450 ℃, the hardness reaches the maximum. The impact energy increases first and then decreases with the increase of tempering temperature. When tempering above 450 ℃, the impact energy increases again. When quenched at 980 ℃ and 1 100 ℃, the maximum wear resistance appears in tempering at 350 ℃, while when quenched at 1 050 ℃, the maximum wear resistance appears at 450 ℃.

关 键 词：定向凝固 过共晶高铬铸铁 热处理 耐磨性 

分 类 号：TG251.2[金属学及工艺—铸造]