Metallurgical Interpretation on Grain Refinement and Synergistic Effect of Mn and Ti in Ti-microalloyed Strip Produced by TSCR  

作　　者：Xin-ping MAO Qi-lin CHEN Xin-jun SUN 

机构地区：[1]College of Materials Science and Metallurgical Engineering,Wuhan University of Science and Technology [2]Institute of Structural Materials,Central Iron and Steel Research Institute

出　　处：《Journal of Iron and Steel Research International》2014年第1期30-40,共11页

摘　　要：The grain refinement mechanism and synergistic effect of Mn and Ti involved in the Ti-microalloying technology of thin slab casting and direct rolling （TSCR） were elucidated. Because the inevitable precipitation of TiN in high Ti-containing liquid steel decreases the volume fraction of TiN precipitated from austenite and the rapid coarse- ning rate leads to a large size of TiN particles, a relatively weak inhibition effect on the recrystallized grain growth was obtained compared with that in the low Ti-containing steel. However, the ferrite grain size in high Ti-containing steel can be refined by the so-called non-recrystallization rolling. The complex addition of Mn and Ti can improve the strength and toughness of strip remarkably, and the mechanisms are that Mn decreases the transformation tempera- ture, refines the ferrite grains, and enhances the formation of bainite and TiC precipitation in ferrite.The grain refinement mechanism and synergistic effect of Mn and Ti involved in the Ti-microalloying technology of thin slab casting and direct rolling （TSCR） were elucidated. Because the inevitable precipitation of TiN in high Ti-containing liquid steel decreases the volume fraction of TiN precipitated from austenite and the rapid coarse- ning rate leads to a large size of TiN particles, a relatively weak inhibition effect on the recrystallized grain growth was obtained compared with that in the low Ti-containing steel. However, the ferrite grain size in high Ti-containing steel can be refined by the so-called non-recrystallization rolling. The complex addition of Mn and Ti can improve the strength and toughness of strip remarkably, and the mechanisms are that Mn decreases the transformation tempera- ture, refines the ferrite grains, and enhances the formation of bainite and TiC precipitation in ferrite.

关 键 词：thin slab casting direct roiling TSCR Ti-microalloying grain refinement precipitation 

分 类 号：TG335.9[金属学及工艺—金属压力加工]