时效温度对GX40CrSi17铁素体耐热铸钢组织的影响  

Effect of aging temperature on microstructure of GX40CrSi17 ferritic heat resistant cast steel

作　　者：李杰 胡建文[1,2] 陆子彤 Li Jie;Hu Jianwen;Lu Zitong(Hebei Province Key Laboratory of Near-net Forming of Materials,School of Materials Science and Engineering,Hebei University of Science and Technology,Shijiazhuang Hebei 050018,China;Steel Ball Technology Innovation Center of Hebei Province,Handan Hebei 057650,China)

机构地区：[1]河北科技大学材料科学与工程学院河北省材料近净成形重点实验室,河北石家庄050018 [2]河北省球磨钢球技术创新中心,河北邯郸057650

出　　处：《金属热处理》2023年第12期36-43,共8页Heat Treatment of Metals

基　　金：石家庄市科技局项目(227790017H)。

摘　　要：为探究时效温度对GX40CrSi17铁素体耐热铸钢组织变化的影响,采用JMatPro软件模拟试验钢的平衡相图和析出相含量随温度的变化,通过光学显微镜、扫描电镜、能谱分析和布氏硬度计,分析了试验钢经不同温度时效后析出相的显微组织及成分与硬度的变化。结果表明,850℃时效,组织为大量较细小颗粒状的M23C6碳化物弥散分布在铁素体基体上,硬度较铸态有所下降;时效温度升至950℃,基体上的M23C6相因回溶数量大幅减少,晶粒尺寸长大,晶界趋向平直化发展;1050℃时效,晶界更为平直,基体组织为铁素体与奥氏体相,硬度随时效温度升高持续降低。To investigate the effect of aging temperature on the microstructure changes of GX40CrSi17 ferrite heat resistant cast steel,JMatPro software was used to simulate the equilibrium phase diagram and precipitation phase content changes with temperature of the tested steel.The microstructure,composition of the precipitation phase,and hardness changes after aging at different temperatures were characterized and analyzed through optical microscopy,scanning electron microscopy,energy spectrum analysis and Brinell hardness tester.The results show that after aging at 850℃,the microstructure is composed of a large number of fine and granular M_(23)C_(6) carbides dispersed in the ferrite matrix,and the hardness decreases compared to that of as-cast.When the aging temperature rises to 950℃,the amount of M_(23)C_(6) phase in the matrix decreases significantly due to re-dissolution,the grain size grows,and the grain boundaries tend to flatten.When aged at 1050℃,the grain boundaries are more straight,and the matrix structure is composed of ferrite and austenite phases.The hardness continues to decrease with the increase of aging temperature.

关 键 词：铁素体耐热铸钢 高温时效 微观组织 热力学模拟 

分 类 号：TG142.7[一般工业技术—材料科学与工程]