淬火回火工艺对Cr26过共晶高铬铸铁组织及性能的影响  

Effect of quenching and tempering process on microstructure and properties of Cr26 hypereutectic high chromium cast iron

作　　者：张凯 张建平 钟宁 卢尚文 Zhang Kai;Zhang Jianping;Zhong Ning;Lu Shangwen(Department of Automotive Engineering,Hunan Industry Polytechnic,Changsha Hunan 410036,China;Sany Heavy Industry Co.,Ltd.,Changsha Hunan 410199,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：《金属热处理》2022年第7期156-163,共8页Heat Treatment of Metals

基　　金：湖南省教育厅科学研究项目(19C0612)。

摘　　要：采用X射线衍射仪、光学显微镜、扫描电镜、硬度测试、冲击试验和磨损试验等手段,研究了淬火和回火工艺对Cr26型过共晶高铬铸铁组织、硬度、冲击吸收能量和耐磨性的影响。结果表明,经980~1100℃淬火和250~600℃回火后的Cr26过共晶高铬铸铁的组织主要是马氏体基体,MC碳化物和少量奥氏体。初生碳化物为六边形,共晶碳化物和回火生成的二次碳化物呈短棒状。总体碳化物含量随淬火温度升高略有上升。随回火温度的升高,硬度先降低后增加,超过500℃回火时再次降低,而冲击吸收能量先增加后降低,超过350℃回火时再次上升。不同温度淬火时,对应最大耐磨性的回火温度不同。980、1050℃淬火时,再经250℃回火获得最高的耐磨性,而1100℃淬火时,再经350℃回火获得最大耐磨性。Effect of quenching and tempering process on the microstructure, hardness, impact absorbed energy and wear resistance of Cr26 hypereutectic high chromium cast iron was studied by means of XRD, OM, SEM, hardness test, impact test and wear test. The results show that the microstructure of the Cr26 hypereutectic high chromium cast iron quenced at 980-1100 ℃ and tempered at 250-600 ℃ is mainly martensite matrix, MCcarbide and a small amount of austenite. The primary carbides are hexagonal, while the eutectic carbides and tempered secondary carbides are short rods. The total carbide content increases slightly with the increase of quenching temperature. With the increase of tempering temperature, the hardness decreases first and then increases, decreasing again when the tempering temperature exceeds 500 ℃, meanwhile, the impact absorbed energy increases first and then decreases, increasing again when the tempering temperature exceeds 350 ℃. For the different quenching temperatures, the tempering temperature corresponding to the maximum wear resistance is different. When quenched at 980 ℃ and 1050 ℃, the maximum wear resistance appears tempered at 250 ℃,while quenched at 1100 ℃,the maximum wear resistance appears tempered at 350 ℃.

关 键 词：过共晶高铬铸铁 热处理 碳化物形貌 耐磨性 

分 类 号：TG156[金属学及工艺—热处理] TG143.1[金属学及工艺—金属学]