M2高速钢铸带组织特征及其后续处理

研究了M2高速钢在不同制备条件下的凝固组织特征以及工业铸带中碳化物在高温热处理、热变形作用下的变化,测量了在不同制备条件下高速钢的凝固速度和共晶碳化物网的厚度,采用透射电镜研究了后续高温热处理、热变形对工业铸带中碳化物相的影响,采用定量金相法分析了制备条件和后续处理工艺对铸带组织的影响.研究结果表明,双辊薄带连铸工艺可以细化高速钢凝固组织的枝晶和共晶碳化物网的厚度,改善碳化物的分布,后续高温热处理和热变形可以进一步优化工业铸带中的碳化物组织.建议在工业铸带的后续处理中同时采用高温热处理和热变形工艺以改善铸带组织.

Microstructure and Post-Treatment of M2 High Speed Steel Cast Strip

The solidification microstructure of M2 high speed steel produced by different technologies and the evolution of carbide in industrial cast 5trip processed by different heat treatment and hot deformation were investigated. The solidification rate and the average thickness of eutectic carbide net were measured, The transmission electron microscopy was adopted to study the influence of subsequent heat treatment and hot deformation on the carbide phase. The effect of different technologies and post processing on the microstructure was analyzed by quantitative metallographic analysis. The results show that application of the twin-roll strip casting technology can refine the dendrite of solidification microstructure, reduce the thickness of eutectic carbide net and improve the carbide distribution in M2 high speed steel. The carbide morphology could be optimized by subsequent heat treatment and hot deformation. It is suggested that both heat treatment and hot deformation should be adopted to improve the M2 cast strip mierostructure.