热处理对2000MPa超高强度不锈钢组织和性能的影响  

Effect of heat treatment on mechanical property of 2000 MPa grade ultra-high strength stainless steel

作　　者：杨哲[1] 曹睿[1] 刘振宝[2] 梁剑雄[2] 胡家齐[2] 

机构地区：[1]兰州理工大学材料学院,甘肃兰州730050 [2]钢铁研究总院特殊钢研究所,北京100081

出　　处：《钢铁》2016年第10期48-53,共6页Iron and Steel

摘　　要：运用Thermal-calc热力学软件、光学显微镜（OM）、扫描电子显微镜（SEM）、透射电子显微镜（TEM）等手段研究了热处理工艺对一种新型的超高强度不锈钢微观组织及力学性能的影响。结果表明,经过固溶处理后钢的基体为高密度位错的板条马氏体组织;强度随着时效温度的升高而逐渐升高,在520~540℃时可达到2 000 MPa,且冲击吸收功在540℃时达到最大值37 J。此时在板条马氏体上析出大量、细小、弥散以μ相为主的第二相,同时在板条与板条界面上有块状的逆转变奥氏体生成,这是该钢具有超高强度与高韧性的主要原因。The effect of heat treatment on microstmctures and mechanical property of a new type ultra-high stainless steel was investigated by means of optical microscopy（OM）, scanning electron microscopy（SEM）, transmission elec- tron microscopy （TEM） combined with Thermal-calc software. The results showed that the matrix of tested steel after solution treatment was lath martensite with high dislocation density. The strength of tested steel gradually increased with the increase of aging temperatures. The ultimate tensile strength eventually reached above 2 000 MPa when aged at temperatures ranging from 520 to 540 ℃. The optimum impact energy with 37 J was obtained after tempering at 540 ℃, Meanwhile, an abundance of fine and dispersive precipitates precipitated in lath martensite which were mainly consisted ofla phase. Moreover, massive reversed austenite formed at the interface of martensite lath. All factors mentioned above result in the ultra-high strength and good toughness of developed steel.

关 键 词：超高强度不锈钢 Μ相 热处理 力学性能 

分 类 号：TG142.71[一般工业技术—材料科学与工程]