固溶处理对53Cr21Mn9Ni4N耐热钢组织及碳化物的影响  

Effect of solid solution treatment on microstructure and carbides of 53Cr21Mn9Ni4N heat-resistant steel

作　　者：王英虎 郑淮北 刘庭耀 宋令玺 白青青 Wang Yinghu;Zheng Huaibei;Liu Tingyao;Song Lingxi;Bai Qingqing(Chengdu Insititute of Advanced Metallic Material Technolgy and Industry Co.,Ltd.,Chengdu Sichuan 610000,China;State Key Laboratory of Metal Material for Marine Equipment and Application,Anshan Liaoning 114009,China)

机构地区：[1]成都先进金属材料产业技术研究院股份有限公司,四川成都610000 [2]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

出　　处：《金属热处理》2022年第4期39-45,共7页Heat Treatment of Metals

摘　　要：利用FactSage软件中的FSstel数据库对53Cr21Mn9Ni4N耐热钢的相图进行计算,分析了氮元素对凝固及冷却过程中相变及析出相的影响,得到了53Cr21Mn9Ni4N耐热钢平衡凝固及冷却相变路径图,并用OM、SEM、XRD、EDS等对53Cr21Mn9Ni4N耐热钢在1200℃固溶3、10、20、40和60 min后的显微组织及碳化物演变规律进行了研究。结果表明,53Cr21Mn9Ni4N耐热钢由1600℃平衡冷却至300℃的过程中完整的平衡相变路径为:液相+气体→液相→液相+δ铁素体→液相+δ铁素体+奥氏体→液相+奥氏体→奥氏体→奥氏体+M_(23)C_(6)→奥氏体+M_(2)(C,N)+M_(23)C_(6)→奥氏体+M_(2)(C,N)+M_(23)C_(6)+α铁素体→奥氏体+M_(2)(C,N)+M_(23)C_(6)+α铁素体+σ相。M_(23)C_(6)的析出温度随着氮含量的增加而降低,M_(2)(C,N)的析出物温度随着氮含量的增加而升高,M_(23)C_(6)会因M_(2)(C,N)的析出受到抑制。53Cr21Mn9Ni4N耐热钢的铸态组织非常不均匀,奥氏体呈树枝晶状生长,枝晶间析出大量层片状碳化物。随着固溶时间的增加,分布在枝晶间的层片状碳化物逐渐变成块状及短棒状,碳化物的数量逐渐减少,粗壮的树枝晶也逐渐变得细小。53Cr21Mn9Ni4N耐热钢在1200℃固溶后的组织及碳化物均得到明显改善。Phase diagrams of 53Cr21Mn9Ni4N heat-resistant steel were calculated by using the FSstel database of FactSage software,the influence of nitrogen on phase transformation and precipitation during solidification and cooling was analyzed,and the equilibrium solidification and cooling phase transformation path diagram of the 53Cr21Mn9Ni4N heat-resistant steel was obtained.The microstructure and carbide evolution of the 53Cr21Mn9Ni4N heat-resistant steel were studied after solution treatment at 1200℃respectively for 3 min,10 min,20 min,40 min and 60 min by OM,SEM,XRD and EDS.The results indicate that the full-phase transformation path of 53Cr21Mn9Ni4N heat-resistant steel during the cooling process from 1600℃to 300℃is as follows:Liquid+Gas→Liquid→Liquid+δ-Ferrite→Liquid+δ-Ferrite+γ-Austenite→Liquid+γ-Austenite→γ-Austenite→γ-Austenite+M_(23)C_(6)→γ-Austenite+M_(2)(C,N)+M_(23)C_(6)→γ-Austenite+M_(2)(C,N)+M_(23)C_(6)+α-Ferrite→γ-Austenite+M_(2)(C,N)+M_(23)C_(6)+α-Ferrite+σ.The precipitation temperature of M_(23)C_(6) decreases with the increase of nitrogen content,the precipitation temperature of M_(2)(C,N)increases with the increase of nitrogen content,and the precipitation of M_(23)C_(6) is inhibited by the precipitation of M_(2)(C,N).The as-cast microstructure of the 53Cr21Mn9Ni4N heat-resistant steel is very uneven,the austenite grows in the form of dendrites and a large number of lamellar carbides precipitate between the dendrites.With the increase of solution treatment time,the lamellar carbides distributed between the dendrites gradually become massive and rod-shaped,the quantity of carbides gradually decreases,and the thick dendrites gradually become finer.The microstructure and carbides of the 53Cr21Mn9Ni4N heat-resistant steel after solution treatment at 1200℃are all obviously improved.

关 键 词：53Cr21Mn9Ni4N耐热钢 固溶处理 碳化物 凝固模式 相图计算 

分 类 号：TG142.1[一般工业技术—材料科学与工程]