一种新型高铝超高碳钢淬回火后的组织和硬度  

Microstructure and hardness of a new ultra-high carbon steel with high Al addition after quenching and tempering

作　　者：王辉[1] 陈清明[1] 张万里 王昌[2] 俞峰[2] 曹文全[2] 

机构地区：[1]昆明理工大学材料科学与工程学院,云南昆明650093 [2]钢铁研究总院特殊钢研究所,北京100081

出　　处：《金属热处理》2017年第12期66-71,共6页Heat Treatment of Metals

基　　金：基金项目:轴承钢冶金质量控制基础理论与产业化关键共性技术研究(2016YFB0300101)

摘　　要：采用扫描电镜、透射电镜和洛氏硬度计等研究了一种含6%Al、1.4%C的超高碳钢(UHCS-6Al)淬火+冷处理+回火后的组织和硬度变化。结果表明:超高碳钢(UHCS-6Al)淬火+冷处理+回火后组织为马氏体组织,峰值硬度高达65.3 HRC;回火时,基体中析出了ε碳化物,析出强化作用显著,而钢中高的Al含量通过抑制ε碳化物向渗碳体转变,显著提高了ε碳化物的稳定性,使试验钢具有优良的回火抗温性能。在200~400℃之间回火时,随回火温度提高,可以保持高的硬度(63 HRC)不变,即使480℃回火2 h后硬度仍有59 HRC。Microstructure and hardness of an ultra-high carbon steel （UHCS-6A1） containing 6wt% A1 and 1.4wt% C were studied after different quenching and tempering treatment by using SEM, TEM and Rockwell hardness tester. The results show that after quenching and tempering, the microstructure of the steel is martensite and its peak hardness is up to 65.3 HRC. The ε carbide separates out in the test steel during tempering, the precipitation strengthening effect of ε carbide is of significance. The high content of A1 improves the stability of carbides significantly by inhibiting the transformation from ε carbide to cementite, which makes the test steel have excellent tempering and temperature resistance. When tempered at 200-400 ℃, the hardness （63 HRC ） remains unchanged with the increase of tempering temperature, even after tempering at 480 ℃ for 2 h, the hardness is still 59 HRC. And the density of the test steel is reduced about 9% than that of the GCrl5 steel.

关 键 词：高铝超高碳钢 淬回火 组织 ε碳化物 硬度 

分 类 号：TG142[一般工业技术—材料科学与工程]