热处理对一种磨球用新型铸钢的组织和性能的影响

制作了一种可用于磨球的新型含钼低铬合金铸钢;测定了经不同工艺热处理后钢的硬度和耐磨性;采用光学显微镜和扫描电镜观察了钢的组织和磨损面形貌。结果表明,钢的淬火硬度随着淬火温度的升高而提高,但淬火温度过高,硬度反而下降。从相同温度淬火后,钢的硬度均随着回火温度的升高而降低。经850℃油淬和300℃回火后,钢的组织为马氏体和少量残留奥氏体,具有较高的硬度和最好的耐磨性。

Effects of Heat Treatment on Microstructure and Property of a New Type of Cast Steel for Grinding Ball

A new type of low-chromium and molybdenum-containing alloy cast steel adaptable to grinding ball was made. After the steel was heat treated with different procedures,the hardness and wearability were measured,and the microstructure and morphology of the worn surface were also observed with OM and SEM. The results show that the as-quenched hardness of steel will increase with the elevation of austenitizing temperature,but the excessively high austenitizing temperature will result in the reduction of hardness.The hardnesses of steel oil-quenched from the same austenitizing temperature all decrease with the elevation of tempering temperature. The Microstructure of steel oil-quenched from 850 ℃ and subsequently tempered at 300 ℃ consists of martensite and a small amount of residual austenite,and has higher hardness and optimum wearability.