奥氏体化温度对含铌热成形钢组织性能的影响  

Effect of austenitizing temperature on microstructure and properties of niobium containing hot-formed steel

作　　者：马光宗 马德刚 李建英 孙璐 王淑华 武冠华 Ma Guangzong;Ma Degang;Li Jianying;Sun Lu;Wang Shuhua;Wu Guanhua(Tangshan Iron&Steel Group Gaoqiang Automobile Plate Co.,Ltd.,Tangshan Hebei 063000,China)

机构地区：[1]唐山钢铁集团高强汽车板有限公司,河北唐山063000

出　　处：《金属热处理》2023年第12期100-104,共5页Heat Treatment of Metals

摘　　要：研究了不同奥氏体化温度下含铌热成形钢的组织和性能变化。结果表明,随着奥氏体化温度的增加,热成形钢的抗拉强度呈先升高后下降的趋势。当在850℃奥氏体化7.5 min时,抗拉强度最高可达1758 MPa,屈服强度为1205 MPa,断后伸长率约为6%,且此时马氏体晶粒最为细小,晶粒尺寸约为2.87μm,马氏体板条间距约为322 nm。随着奥氏体化温度的升高,基体组织奥氏化程度逐渐增加,(Nb,Ti)复合碳氮化物析出粒子同时也逐渐发生回溶,奥氏体晶粒粗化。当在930℃奥氏体化5.0 min时,马氏体晶粒增大到4.936μm,马氏体板条间距增大到929.6 nm。Microstructure and properties of hot formed steel containing niobium austenitized at different temperatures were studied.The results show that the tensile strength of the hot formed steel increases first and then decreases with the increase of austenitizing temperature.When austenitized at 850℃for 7.5 min,the tensile strength up to 1758 MPa,the yield strength is 1205 MPa,and the elongation is about 6%,and the martensite grain is the smallest,about 2.87μm,and the martensitic lath is about 322 nm.With the increase of austenitizing temperature,the austenitizing degree of matrix structure gradually increases,and the precipitation of(Nb,Ti)composite carbon nitride particles also gradually redissolve,and the austenite grains are coarsened.When austenitized at 930℃for 5.0 min,the martensite grain increases to 4.936μm,and the martensitic lath increases to 929.6 nm.

关 键 词：奥氏体化温度 热成形钢 抗拉强度 显微组织 析出粒子 

分 类 号：TG142.24[一般工业技术—材料科学与工程]