低合金高强度钢奥氏体相中碳氮化物的析出模型

Carbo-Nitride Precipitation Model in Austenite of HSLA Steel

采用规则溶液描述低合金高强度钢奥氏体相中碳氮化物的热力学性质,以经典形核理论为基础,建立了低合金高强度钢奥氏体相中碳氮化物在连续冷却过程中碳氮化物析出模型。计算结果表明:冷却速率对碳氮化铌的析出及长大有重要影响。在不同冷却条件下,碳氮化铌的析出量随反应时间呈先增加后减少的趋势;随着冷却速率的提高,达到析出量峰值的时间越短,析出量和析出粒子的平均直径均减小。

Base on regular solution model and traditional nucleation theory, carbo-nitride precipitation model in austenite of HSLA steel during continuous cooling process is developed. As a result, It is found that the cooling rate has great effect on the Nb（CN） nucleation and growth. The precipitation amount of Nb（CN） particle increases firstly and then decreases at different cooling rate. The faster the cooling rate and the shorter the time to reach the precipitation amount peak value, the smaller are the precipitation amount and the mean diameter of particles.