|
Hokkaido University Collection of Scholarly and Academic Papers >
Graduate School of Engineering / Faculty of Engineering >
Peer-reviewed Journal Articles, etc >
As-cast Austenite Grain Structure in Al Added 0.2 wt% Carbon Steel
| Title: | As-cast Austenite Grain Structure in Al Added 0.2 wt% Carbon Steel |
| Authors: | Kencana, Surya Browse this author | | Ohno, Munekazu Browse this author →KAKEN DB | | Matsuura, Kiyotaka Browse this author →KAKEN DB | | Isobe, Kohichi Browse this author |
| Keywords: | carbon steel | | solidification | | δ-γ transformation | | grain refinement | | aluminum | | phosphorous | | segregation | | pinning effect |
| Issue Date: | 15-Feb-2010 |
| Publisher: | Iron and Steel Institute of Japan |
| Journal Title: | ISIJ International |
| Volume: | 50 |
| Issue: | 2 |
| Start Page: | 231 |
| End Page: | 238 |
| Publisher DOI: | 10.2355/isijinternational.50.231 |
| Abstract: | Effects of Al addition on as-cast γ-austenite grain structure in 0.2wt%C–0.035wt%P steel with Al concentration ranging from 0.04 to 1.04 wt% were studied by means of furnace cooling and casting experiments. In the furnace cooling experiment with a cooling rate of 0.03°C/s, the as-cast γ grain structure consisted of equiaxed grains and the γ grain size was not affected by the increase in Al concentration up to 0.54 wt%. In the casting experiment of the sample with 0.04 wt% Al, on the other hand, the as-cast γ grain structure consisted of Coarse Columnar Grain (CCG), Fine Columnar Grain (FCG) and Equiaxed Grain (EG) regions, sequentially, from the mold side to the center of the ingot. The increase in Al concentration leads to increase in the fraction of FCG region at the expense of both CCG and EG regions. Even in the samples with high Al concentrations, AlN particles were rarely found and also Al segregation did not occur substantially. Instead, P segregated in interdendritic regions. The concentration of the segregated P increased from the CCG region to the FCG region. It was suggested based on a thermodynamic calculation that the segregation of P is enhanced by Al addition and the high P concentration stabilizes the high temperature phase such as liquid or δ-ferrite, depending on Al concentration at lower temperatures. This stabilized high temperature phase is considered to retard the γ grain boundary migration. Therefore, the increase of FCG region and the decreases of CCG and EG regions due to Al addition should be attributable to pinning effect of the stabilized high temperature phase. |
| Rights: | 著作権は日本鉄鋼協会にある |
| Type: | article |
| URI: | http://hdl.handle.net/2115/75409 |
| 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)
|
Submitter: 大野 宗一
|
