Austenite grain growth simulation considering the solute-drag effect and pinning effect.
The pinning effect is useful for restraining austenite grain growth in low alloy steel and improving heat affected zone toughness in welded joints. We propose a new calculation model for predicting austenite grain growth behavior. The model is mainly comprised of two theories: the solute-drag effect and the pinning effect of TiN precipitates. The calculation of the solute-drag effect is based on the hypothesis that the width of each austenite grain boundary is constant and that the element content maintains equilibrium segregation at the austenite grain boundaries. We used Hillert's law under the assumption that the austenite grain boundary phase is a liquid so that we could estimate the equilibrium solute concentration at the austenite grain boundaries. The equilibrium solute concentration was calculated using the Thermo-Calc software. Pinning effect was estimated by Nishizawa's equation. The calculated austenite grain growth at 1473-1673 K showed excellent correspondence with the experimental results.
Research & Development, Nippon Steel & Sumitomo Metal Corporation, Ltd , Futtsu , Japan.
Naoto
N
Fujiyama
Research & Development, Nippon Steel & Sumitomo Metal Corporation, Ltd , Amagasaki , Japan.
Toshinobu
T
Nishibata
Nippon Steel & Sumikin Technology Co., Ltd. , Amagasaki , Japan.
Akira
A
Seki
Research & Development, Nippon Steel & Sumitomo Metal Corporation, Ltd , Futtsu , Japan.
Hiroyuki
H
Hirata
Research & Development, Nippon Steel & Sumitomo Metal Corporation, Ltd , Futtsu , Japan.
Kazuhiro
K
Kojima
Nippon Steel & Sumikin Technology Co., Ltd. , Amagasaki , Japan.
Kazuhiro
K
Ogawa
10 Engineering and structural materials; 100 Materials; 106 Metallic materials; 400 Modeling / simulations; Austenite grain growth; HAZ; low carbon steel; phase-field method; pinning effect; solute-drag effect