Effect of Dissolved and Precipitated Niobium in Microalloyed Steel on Deformation Induced Ferrite Transformation(DIFT)

作     者：LIU Qing-you DENG Su-huai SUN Xin-jun DONG Han WENG Yu-qing 

作者机构：Central Iron and Steel Research Institute Beijing 100081 China Chinese Society for Metal Beijing 100711 China 

出 版 物：《Journal of Iron and Steel Research International》 (JOURNAL OF IRON AND STEEL RESEARCH,INTERNATIONAL)

年 卷 期：2009年第16卷第4期

页      面：67-71页

核心收录：

学科分类：080503[工学-材料加工工程] 08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0802[工学-机械工程] 080201[工学-机械制造及其自动化] 

基　　金：Item Sponsored by National Key Technologies Research and Development Program of China(G1998061502) 

主　　题：niobium precipitation recrystallization deformation induced ferrite transformation 

摘      要：Hot deformation processing was designed to study the effects of niobium （Nb） on DIFT. A prestrain of 0.51 at 880 ℃ for different isothermal time was used for adjusting the deformed austenite constitution and Nb existing state, followed by a secondary heavy deformation at 780 ℃ for inducing the ferrite transformation. The volume fraction and grain size of deformation induced ferrite （DIF） obtained at different isothermal time between double hits were investigated. It was found that Nb dissolved in austenite is adverse to DIFT; however, the precipitation of Nb is beneficial to DIFT. As Nb plays the role in the conventional TMCP, Nb retards the recrystallization of deformed austenite and enhances the deformation stored energy in the multipass deformation, and in result, Nb promotes DIFT.