Cr8Mo2SiV钢中碳化物析出行为的原位观察  

In-situ observation of carbide precipitation behavior in Cr8Mo2SiV steel

作　　者：贺帅 洪晓莉 赵金环 刘鑫 秦哲 王军生 He Shuai;Hong Xiaoli;Zhao Jinhuan;Liu Xin;Qin Zhe;Wang Junsheng(State Key Laboratory of Metal Material for Marine Equipment and Application,Anshan Liaoning 114009,China;Ansteel Beijing Research Institute Co.,Ltd.,Beijing 102200,China;Qingdao NMEI Group Co.,Ltd.,Qingdao Shandong 266000,China)

机构地区：[1]海洋装备用金属材料及其应用国家重点实验室,辽宁鞍山114009 [2]鞍钢集团北京研究院有限公司,北京102200 [3]青岛海检集团有限公司,山东青岛266000

出　　处：《金属热处理》2025年第3期214-219,共6页Heat Treatment of Metals

基　　金：国家自然科学基金(U2141207)。

摘　　要：以高碳中铬的Cr8Mo2SiV莱氏体冷作模具钢为研究对象,采用高温激光共聚焦显微仪原位观察了共晶碳化物(M_(7)C_(3))和二次碳化物(M_(7)C_(3))在加热、保温和冷却过程中的演变规律。结果表明,当加热温度高于1180℃时,低熔点共晶相回熔,晶界周围出现明显的过热和过烧现象,而且保温温度越高,冷却过程中二次碳化物开始析出的温度越高。随着保温温度由1160℃升高至1200℃,晶界上富Mo的颗粒状亚稳态碳化物溶解,长条枝状二次碳化物上富集的合金元素不断向基体内部扩散,使得基体与碳化物中合金元素的含量差异逐渐缩小。Focusing on Cr8Mo2SiV ledeburite cold working die steel with high carbon and medium chromium content,the evolution of eutectic carbides(M_(7)C_(3))and secondary carbides(M_(7)C_(3))during the process of heating,holding and cooling was in-situ observed by using a high-temperature laser scanning confocal microscope.The results show that when the heating temperature exceeds 1180℃,the low-melting eutectic phase undergoes remelting,leading to pronounced overheating and overburning phenomena around the grain boundaries.Furthermore,The higher the holding temperature is,the higher the precipitation temperature of secondary carbides during the cooling process is.As the holding temperature rises from 1160℃to 1200℃,Mo-rich particulate metastable carbides located at the grain boundaries dissolve,and the alloy elements enriched in the elongated dendritic secondary carbides continuously diffuse into the matrix.The difference in alloy element content between the matrix and the carbides is reduced gradually.

关 键 词：冷作模具钢 碳化物 原位观察 析出形貌 

分 类 号：TG156[金属学及工艺—热处理]