基于数学模型的Nb微合金钢中铁素体相变研究

Ferrite Phase Transition of Nb Microalloyed Steel Based on Mathematical Model

根据热力学和动力学的基本理论,建立了低温条件下形变诱导Nb微合金钢中铁素体相变的数学模型,并研究了热变形和化学成分对铁素体体积分数和晶粒尺寸的影响。结果表明,降低变形温度和增加变形程度都能够促进α相变,增加铁素体体积分数,细化铁素体晶粒。而C和Mn含量的增加会抑制α相变过程。最后将模型应用到热轧带钢生产中,其模拟值与实测值吻合较好。

The mathematical model on the ferrite phase transition of Nb microalloyed steel induced by the low-temperature deformation was established, according to the basic theory of thermodynamics and dynamics. And the effect of the thermal deformation and chemical composition on the volume fraction and grain size of the ferrite was investigated. The results show that a phase transition increases with the decrease of the deformation temperature and the increase of the deformation extent, and thus the volume fraction of the ferrite increases and the grain is refined. But the increase of C and Mn content suppresses α phase transition. And the simulated values are good agreed with the experimental ones when the model is applied into the production of hot rolling strip steel.