ZrC粒子对低碳钢形变诱导相变热力学条件的影响

Effects of ZrC Particles on Thermodynamic Conditions of Low Carbon Steel during Deformation Induced Ferrite Transformation

采用单向压缩热模拟实验,研究了ZrC粒子对低碳钢形变诱导铁素体相变热力学条件的影响。研究结果表明:将适当粒径和体积分数的ZrC粒子作为形变和再结晶核心,能提高相变的开始温度,降低相变的临界变形量,从而提高α-Fe形核率,使铁素体晶粒超细化;ZrC粒子的数量对形核的促进作用存在某一临界值,过量的粒子不利于组织细化。基于相变热力学理论,制定了实验室轧制工艺,获得了铁素体晶粒尺寸达3.9μm的低碳钢中厚板,所得材料的综合性能显著提高。

The effects of ZrC particles on thermodynamic conditions of low carbon steel during DIFT were studied by unidirectional compression thermal simulating experiment. The results show that ZrC particles with definite radius and suitable volume fraction as the nucleus of deformation and recrystallization,it can improve the start temperature and reduce critical deformation of DIFT, and greatly improve α-Fe nucleating rate which leads to the ferrite grains further refinement. However, the role of ZrC particles in promoting nucleation exists a critical value, an excessive amount of particles will produce inhibition of ferrite core, it is not conducive to the organization refinement. Based on thermodynamic theory of phase transitions, a laboratory rolling process is developed, and obtains the ferrite grain size of low carbon steel plate up to 3.9μm, material yield strength reached 802MPa, it significantly improves overall performance.