Microstructure and mechanical properties of F_(GBA)/B_G air cooling bainitic steels containing niobium  

作　　者：Chun Feng Hong-sheng Fang Bing-zhe Bai Yan-kang Zheng 

机构地区：[1]Department of Materials Science and Engineering, Tsinghua University, Beijing 100084, China

出　　处：《International Journal of Minerals,Metallurgy and Materials》2010年第4期429-434,共6页矿物冶金与材料学报（英文版）

基　　金：supported by the National Key Technologies R&D Program of China(No.2004CB619105)

摘　　要：The effect of different Nb additions on the mechanical properties and microstrucmre evolution of grain boundary allotriomorphic ferrite （FGBA） / granular bainite （BG） air cooling bainitic steels was investigated. The results indicate that the tensile strength and yield strength increase by 157 and 97 MPa, respectively with the addition of 0.02wt% Nb. The steel acquires superior strength and toughness with the addition of 0.06wt% Nb. The results of scanning electron microscopy and transmission electron microscopy reveal that the addition of Nb not only refines the size of granular bainite but also increases the volume fraction of granular bainite in FGBA/BG steels. The refinement effect of granular bainite is improved with the increase of Nb content.The effect of different Nb additions on the mechanical properties and microstrucmre evolution of grain boundary allotriomorphic ferrite （FGBA） / granular bainite （BG） air cooling bainitic steels was investigated. The results indicate that the tensile strength and yield strength increase by 157 and 97 MPa, respectively with the addition of 0.02wt% Nb. The steel acquires superior strength and toughness with the addition of 0.06wt% Nb. The results of scanning electron microscopy and transmission electron microscopy reveal that the addition of Nb not only refines the size of granular bainite but also increases the volume fraction of granular bainite in FGBA/BG steels. The refinement effect of granular bainite is improved with the increase of Nb content.

关 键 词：granular bainite microstructure evolution mechanical properties NB 

分 类 号：TG142.2[一般工业技术—材料科学与工程] TM311[金属学及工艺—金属材料]