铸态微合金钢第二相粒子析出机制及耦合模型研究

我国引入微合金钢技术以来，微合金钢被广泛应用到各个领域，然而第二相粒子析出物严重影响了铸态微合金钢的质量。为了深入了解第二相粒子析出机理，为解决铸坯质量提供理论支持，本项目通过对溶质偏析、枝晶、第二相粒子研究，建立第二相粒子析出耦合模型，阐明铸态微合金钢第二相粒子析出机理；通过研究铸坯反复热变化对第二相粒子的影响，揭示第二相粒子在二冷区热循环影响下的析出机制；通过研究沿液相穴铸坯凝固特性，预测第二相粒子析出规律及分布特征；通过研究铸坯凝固过程综合受力情况，阐明第二相粒子诱导析出机理。综合前述研究，建立第二相粒子析出耦合模型，进而为解决铸坯缺陷提供工艺技术原理。

Microalloy steel has been utilized in difference areas since it was introduced to china. however, there are many quality defects which has limited the development of microalloy steel. Several reports proved that the main influence factors on slab quality caused by second phase particles. In order to study on precipitation mechanism of second phase particle, coupling model of second phase particles shuold be established according to reseach on relationship between solute segregation, dendrites and second phase particle; precipitation mechanism of second phase particles was revealed by researching on the thermal cycling in slab; study on solidified characterization along the liquid core and predict the distribution character of second phase particle; principle of strain induced precipitation was clarified the by researching on force condition of slab during solidifaction. All the analysis shows that defects in continuous casting can be solved by coupling model of second phase particles precipitate.