| Title |
Research Paper - Transformations - : Influence of Cooling Method of Continuous - cast Slabs on the Austenite Grain Growth Behavior of Ti - microalloyed Steel During Reheating |
| Authors |
윤여분(Yeo Boon Yoon); 박중근(Joong Keun Park); 유장용(Jong Yong Yoon); 강기봉(Ki Bong Kang); 주웅용(Wung Yong Choo) |
| Abstract |
The influence of cooling method of continuous-cast slabs on the grain growth behavior of Ti-microalloyed steel during reheating to the austenite region has been studied using optical microscope and transmission electron microscope. The reheated structure of air-cooled continuous-cast slabs exhibits the austenite grain sizes ranging from 30 to 40㎛ and a fine uniform distribution of TiN particles from 10 to 20 ㎚. The grain coarsening temperature(GCT) ranges from 1250℃ at the slab center to 1300℃ at inbetween the surface and center. The values of GCT are in good agreement with the prediction of Gladman model. On the other hand, the reheated structure of water-cooled continuous-cast slabs shows a rather low GCT(1150℃∼1250℃). This is because this structure consists of bimodal TiN particle size distribution of coarse particles(30∼45 ㎚) and fine particles(5∼20 ㎚). The reason for this is believed to be owing to the fact that the water cooling of the continuous-cast slab effectively suppresses the occurrence of continuous particle nucleation during cooling and only enhances the growth rate of particles formed prior to the water cooling stage. |