低碳低合金铸钢力学性能的研究

Study of LALC CrMnSi Cast Steel on Mechanical Property

利用Olympus光学显微镜、扫描电镜(SEM)及能谱分析(EDAX)探讨了等温淬火工艺对低碳低合金CrMnSi铸钢力学性能的影响,并通过XRD定量分析了相的组成。结果表明,合适的等温淬火工艺,可获得一定数量的贝氏体和残余奥氏体(约6%)的复合组织,冲击断口形貌由解理刻面变为韧窝状,铸造成形无缺口试样(10 mm×10 mm×55 mm)的冲击韧度由αk≤30 J/cm2 增加至αk≥170 J/cm2,硬度HRC≥40,具有较高硬度和冲击韧度的配合。

The Olympus microscope, scanning electron microscope and EDAX were used to investigate the influence of isothermal quenching process of low-alloy, low carbon (LALC) CrMnSi cast steel on mechanical property, meantime, quantitative analysis of composite phases by XRD. The results show that the duplex microstructure consisting of Bainite and residual Austenite can be obtained through the optimum isothermal quenching, the fractographies of specimens changed from cleavage facets to dimple with impact toughness increasing, the impact toughness increased from 30 J/cm2 to 170 J/cm2, and hardness is greater than 40(HRC).