|
Hokkaido University Collection of Scholarly and Academic Papers >
Graduate School of Engineering / Faculty of Engineering >
Peer-reviewed Journal Articles, etc >
Effects of Fine Precipitates on Austenite Grain Refinement of Micro-alloyed Steel during Cyclic Heat Treatment
| Title: | Effects of Fine Precipitates on Austenite Grain Refinement of Micro-alloyed Steel during Cyclic Heat Treatment |
| Authors: | Saito, Genki Browse this author →KAKEN DB | | Sakaguchi, Norihito Browse this author →KAKEN DB | | Ohno, Munekazu Browse this author →KAKEN DB | | Matsuura, Kiyotaka Browse this author →KAKEN DB | | Takeuchi, Masayoshi Browse this author | | Sano, Taichi Browse this author | | Minoguchi, Koki Browse this author | | Yamaoka, Takuya Browse this author |
| Keywords: | grain refinement | | reverse transformation | | cyclic heat treatment | | precipitation |
| Issue Date: | 15-Nov-2019 |
| Publisher: | The Iron and Steel Institute of Japan |
| Journal Title: | ISIJ international |
| Volume: | 59 |
| Issue: | 11 |
| Start Page: | 2098 |
| End Page: | 2104 |
| Publisher DOI: | 10.2355/isijinternational.ISIJINT-2019-153 |
| Abstract: | The effects of fine precipitates on the austenite grain refinement of micro-alloyed steel during cyclic heat treatment were investigated under different solution treatments. After three rounds of cyclic heat treatment of A(c3) and A(r3) transformations of the as-received steel rod with rapid heating and cooling, the austenite grain size was 3-10 mu m. On the other hand, three rounds of cyclic heat treatment after solution treatment at 1 300 degrees C reduced the austenite grain size to 2-5 mu m. The as-received sample included AIN-Ti(C,N)-MnS composite particles with a mean diameter of 30 nm and a number density of 11 mu m(-3), and the mean diameter did not change during cyclic heat treatment. Thus, it was considered that the reduction in austenite grain size without solution treatment was caused by the increase in the nucleation site of austenite phase with increasing number of cycles, due to the refinement of the prior austenite grains with martensitic structure during the cyclic heat treatment. When solution-treated at 1 300 degrees C, the AIN-Ti(C,N)-MnS composite particles were solved, and they were precipitated during the cyclic heat treatment with a mean diameter of 12 nm and an increased number density of 85 mu m(-3). Thus, it was considered that the further reduction in austenite grain size with solution treatment was caused by the pinning effect of the fine precipitates, in addition to the increase in the number of austenite phase nucleation sites with increasing number of heat treatment cycles. |
| Type: | article |
| URI: | http://hdl.handle.net/2115/76499 |
| Appears in Collections: | 工学院・工学研究院 (Graduate School of Engineering / Faculty of Engineering) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
|
|
