W18Cr4V钢真空气淬和普通油淬的组织与性能比较

采用真空气淬法和普通空气加热油淬法分别对W18Cr4V钢进行热处理。利用金相显微镜和洛氏硬度计对热处理后W18Cr4V高速钢的组织和硬度进行了比较观察和测试分析。结果表明,两种淬火工艺处理的试样组织基本一致,均为隐晶形的淬火马氏体基体组织、大颗粒状的共晶碳化物和细小点粒状的二次碳化物及残留奥氏体,气淬后的组织更均匀;回火后的组织也很相似,为回火马氏体及未溶解的共晶碳化物和二次碳化物。经真空气淬的试样硬度（65HRC）仅比普通空气加热油淬的（66HRC）略有降低,但能满足工模具的硬度要求,而且试样表面光洁,呈银灰色,变形微小,对于要求精度不太高的零件,无需进行后续加工,对环境也无污染。

Comparison of Microstructure and Properties of W18Cr4V Steel Between Vacuum Gas Quenching and Conventional Oil Quenching

W18Cr4V steel was heat-treated by vacuum gas quenching and conventional oil quenching respectively. The microstructure and hardness ofWl 8Cr4V steel after different heat treatment were observed and tested by means of optical microscope and hardness measurement. The results show that the microstructure of W 18Cr4V steel is similar after different heat treatment, which present quenched martensite, fine carbonate and retained austenite after quenchings and tempered martensite and undissolved carbonate after tempering. It is also show the hardness achieved by gas quenching is lower than that by oil quenching slightly, but it can satisfy the specification of tool and die. Furthermore the silvery-gray surface of the sample after gas quenching is much cleaner and the level of geometrical distortion is much tinier than that after oil quenching. There is no need for follow-up treatments for low-precision parts and there is no pollution on the environment.