变质低铬白口铸铁的强韧化及耐磨性研究

Study on Strengthening and Toughening and Wear Resistance of Modified Low Chromium White Cast Iron

通过在铸造过程中对熔体进行复合变质处理,制备了变质低铬白口铸铁。采用金相、断口形貌分析、洛氏硬度(HRC)测试、冲击韧度测量等方法分析了不同热处理状态下低铬白口铸铁组织性能变化,采用摩擦磨损的方法对比了低铬白口铸铁与高锰钢及合金钢的耐磨性。结果表明,通过复合变质处理可以有效改善碳化物的形态与分布,变质低铬白口铸铁经850℃淬火及350℃回火处理后,可以获得优良的综合力学性能,其HRC硬度值为56.5,冲击韧度值为11.0 J/cm2,经强韧化处理后的低铬白口铸铁具有优良的耐磨性能。

Low chromium white cast iron samples were process. The mechanical properties and microstructures prepared by complex modification of the melt during the casting under different heat treatment circumstance were investigated by metallographical analysis, scanning electron microscope, Rockwell hardness measurement and impact toughness test. Friction and wear test was made for wear resistance comparision among low chromium white cast iron, high-manganese steel and alloy steel. The results showed that the morphology and distribution of the carbides were well improved by complex modification. After being quenched at 850 ℃ and tempered at 350℃, the modified white cast iron got excellent comprehensive mechanical properties. Its Rockwell hardness and impact toughness are 56.5 and 11.0 J/cm^2, respectively. The strengthened and toughened low chromium white cast iron has excellent wear resistance.