材料期刊网

通过考虑Si、Mn元素对Nb析出动力学的影响，对DS析出模型进行了修正，并采用等温应力松弛法进行试验测定，研究了中碳Nb微合金钢的应变诱导析出规律。实验结果表明：采用两种方法得到的PTT曲线具有典型的”C”型特征，且曲线形状基本吻合；沉淀析出的鼻子温度在900℃左右，并随着应变速率的增大，PTT曲线左移，析出孕育期缩短。

The strain induced precipitation of medium-carbon Nb microalloyed steel was investigated by the stress relaxation method and DS precipitation kinetics model, the effects of Si and Mn on the precipitation kinetics of Nb carbonitride added to the DS equation. The results show that the caculated precipitation-time-temperature PTT diagrams are in good agreement with experimental results obtained from isothermal stress relaxation, and the shape of PTT is typical C curve; The fastest precipitation was about 900℃, strain rate accelerates the precipitation kinetics and shifts the PTT diagrams leftside.