铁素体不锈钢410S与430高温相组织的Thermo-calc计算与试验研究

通过金相观察与DSC试验,对410S和430两种铁素体不锈钢的高温组织进行了研究,并通过定量分析,分别获得了高温相组织的体积分数及与温度的变化关系.利用Thermo-calc热力学软件,计算了两钢种的高温相图,计算结果和试验结果吻合较好.由于高温下铁素体不锈钢存在两相组织,钢的热塑性会降低,导致轧制时产生边裂,故探讨了通过热加工工艺优化来避免边裂的问题.

Thermo-calc Calculation and Experimental Research on Microstructure of 410S and 430 Ferritic Stainless Steels at High Temperature

The microstructures of 410S and 430 ferritic stainless steels at high temperature were studied by means of optical microscope and DSC. With the help of quantitative analysis, the relationship between volume fraction of each phases and temperature was obtained. The thermodynamic calculation for the phase diagram of these two steels at high temperature was carried out by means of Thermo-calc and the calculation results agreed well with the experiments. Because of the duplex microstructure at high temperature, the hot ductility of ferritic stairless steel would decrease, which would lead to edge-cracking in the process of hot rolling. The optimization of hot working parameters used to avoid the edge-cracking was discussed.