贝氏体机械用钢的回火工艺研究  

Study on Tempering Process of Bainite Mechanical Steel

作　　者：徐立华[1] 殷铭[1] 

机构地区：[1]苏州工业职业技术学院,江苏苏州215104

出　　处：《热加工工艺》2016年第2期183-184,189,共3页Hot Working Technology

基　　金：苏州市科技局软科学课题(SR201240)

摘　　要：通过对贝氏体机械用钢回火后金相显微组织的观察和洛氏硬度的测量,研究了回火对组织和综合性能的影响。结果表明,热轧态试验钢经回火处理后,随回火温度的升高,显微组织中的板条状马氏体发生溶解,直至分解完全,位错密度降低;回火后组织中晶粒尺寸随碳元素从奥氏体中析出,晶粒尺寸变得细小,起到了强化作用;但随温度的继续升高,板条状马氏体溶解完全,碳化物析出所产生的强化作用已经不再明显;随回火温度升高,试验钢的硬度出现降低趋势。Effects of tempering on the microstructure and rock-well hardness of bainite mechanical steel were studied by microstructure observation and hardness measuring. Experimental results show that the microstructure of lath martensite continuously dissolves until completely decomposed with the increase of temperature and the dislocation density is reduced; The grain size becomes smaller as carbon precipitated from the austenite, and it played a role in strengthening; But with the increase of intermittent temperature, the lath martensite is completely dissolved, the effect of carbide precipitation is no longer evident; The hardness of the steel specimens decreases with the imcrease of temperature.

关 键 词：贝氏体 机械用钢 回火工艺 洛氏硬度 

分 类 号：TG156.3[金属学及工艺—热处理]