【摘要】 使用不同淬冷烈度的淬火介质对车轴用EA4T和35CrMo钢进行淬火处理,然后利用金相显微镜、透射电子显微镜等分析钢的组织结构,并测定其力学性能.结果表明:随着淬冷烈度的增加,EA4T和35CrMo钢在淬火后获得的马氏体组织越细小,硬度有所增加,但变化幅度不大;虽然液氮具有很高的淬冷烈度,但在淬火过程中易形成蒸汽膜而导致冷速降低,形成非马氏体组织.35CrMo钢淬火形成的马氏体为体心正方结构,其轴比c/a随着淬冷烈度的增大呈小幅度增大,碳的过饱和度随着淬冷烈度的增大而增大.35CrMo钢经不同淬冷烈度的淬火介质淬火后回火,其力学性能主要取决于回火温度,碳的过饱和度对回火钢的性能影响不显著.更多还原

【Abstract】 EA4T and 35CrMo steels were quenched by quenching medium with different quenching intensity.Then the microstructure of the steels was analyzed by metallographic microscope and transmission electron microscope,and its mechanical properties were also measured. The results show that,in EA4T and 35CrMo steels,with the increase of quenching intensity,finer martensite is obtained after quenching,but the hardness is increased a little. Although liquid nitrogen has high quenching intensity,it is easy to form vapor film in the course of quenching,which leads to the decrease of cooling rate and the formation of non martensite. The martensite formed in 35CrMo steel by quenching is a tetragonal structure,and its axial ratio c/a increases slightly with the increase of quenching intensity,and the supersaturation of carbon is increased with the increase of quenching intensity. The mechanical properties of the 35CrMo steel quenched by quenching medium with different quenching intensity mainly depend on the tempering temperature. The supersaturation of carbon has no significant influence on the properties of the tempered steel.更多还原