深冷处理对M2高速钢微观组织演化影响的内耗研究  

The Study of the Internal Friction on the Effect of Microstructure Evolution of Cryogenic Treated M2 High Speed Steel

作　　者：周龙梅[1,2] 闵娜[1,2,3] 李宏模[1,2] 谢尘[1,2] 李洁[1] 吴晓春[1,2,4] 

机构地区：[1]上海大学材料科学与工程学院,上海200072 [2]上海市钢铁冶金新技术开发应用重点实验室,上海200072 [3]微结构重点实验室,上海200072 [4]省部共建高品质特殊钢冶金与制备国家重点实验室,上海200072

出　　处：《模具制造》2017年第2期89-92,共4页Die & Mould Manufacture

基　　金：上海市教委国外访学项目(51301100)

摘　　要：采用纳米力学测试系统以及内耗等测试方法,研究了不同深冷处理时间对M2高速钢微观组织结构的影响。结果显示,深冷处理1 h后M2钢具有最优的耐磨性能,深冷处理后的耐磨性能均优于常规热处理。结合内耗结果发现深冷1 h后SKK峰最高;深冷时间延长,SKK峰逐渐降低。研究结果表明,深冷处理前期M2钢中的残余奥氏体转变为马氏体,增加了基体的硬度;而随着深冷时间增加,在等温过程中形成等温马氏体,等温时效作用下钢中可动位错数量减少导致M2钢耐磨性能降低。The paper used nano scratch and internal friction to investigate the microstructure of M2 high speed steel after cryogenic treatment （DCT）. The results indicated that the wear resistance of M2 high speed steel reached the optimal after soaked for lh, and wear resistance after cryogenic treatment was better than that of conventional heat treatment. Combined with the internal friction results, we found that SKK peak reached maximum after soaked for 1h, and with the increasing of the cryogenic time, SKK peak was damping. Early stage during the cryogenic treatment, it indicated that retained austenite phase turned into martensite phase of in the M2 steel, which lead to the increasing of the hardness of the matrix phase. With the cryogenic time increased, isothermal martensite formation in isothermal process, and because of the aging process, the decreasing of movable dislocation in martensite phase result in the damp of the wear resistance in the M2 steel.

关 键 词：深冷处理 M2高速钢 微观组织 内耗 纳米划痕 

分 类 号：TG142.1[一般工业技术—材料科学与工程] TG161[金属学及工艺—金属材料]