高碳铬钢凝固及热处理组织演变规律

摘要：系统研究了高碳铬钢复合轧辊工作层材质在凝固及热处理过程的组织演变规律。利用Thermo Calc软件进行平衡相图计算，阐明了平衡凝固过程及冷却过程中碳化物析出行为。通过热膨胀仪精确测定了奥氏体化温度对合金相变点的影响，获得了珠光体等温转变动力学曲线。结合扫描电镜、能谱分析和X射线衍射分析，确定了热处理工艺对最终显微组织的影响，明确了凝固过程中形成的一次碳化物M7C3和二次碳化物对热处理组织的影响规律，为高碳铬钢复合轧辊工作层材料的实际热处理工艺制定提供理论依据。

Microstructure evolution of high carbon and chromium steel during solidification and heat treatment

The microstructure evolution of high chromium steel used as the working layer of composite roll materials during solidification and heat treatment was studied systematically. The equilibrium phase diagram was calculated by Thermo-Calc software to clarify the precipitation behavior of carbides in the process of equilibrium solidification and cooling. The effect of austenitizing temperature on the phase transformation behavior was accurately measured by thermal dilatometer, and the isothermal transformation kinetic curve of pearlite was obtained. Combined with scanning electron microscope, energy dispersive spectrometer and X ray diffraction analysis, the effect of heat treatment process on the final microstructure is determined, and the effect of primary carbide M7C3 and secondary carbide formed during solidification on the heat treatment structure is clarified, which provides a theoretical basis for the practical heat treatment process of high chromium steel composite roll working layer material.