论文部分内容阅读
对一种新型含氮奥氏体模具钢在不同工艺下进行热处理,并对试验钢的强韧性与热稳定性进行测试。利用DIL805A热膨胀相变仪测定膨胀系数,通过光学显微镜、高分辨扫描电子显微镜、X射线衍射仪及高分辨透射电子显微镜观察分析显微组织。结果表明:试验钢的最佳热处理工艺为1200℃固溶+720℃时效保温2 h,硬度达46 HRC,横向无缺口冲击试样冲击功达150 J;热稳定性良好,700℃保温20 h,硬度基本不变,780℃保温20 h后,硬度在44 HRC以上;钢中析出相主要为V(C、N),时效状态下析出相占钢中总量约4%,弥散析出强化相尺寸为10～20 nm。
A new type of nitrogen-containing austenitic die steel was heat-treated under different processes and the toughness and thermal stability of the test steel were tested. The expansion coefficient was measured by DIL805A thermal expansion phase change instrument, and the microstructure was analyzed by optical microscope, high resolution scanning electron microscope, X-ray diffraction and high-resolution transmission electron microscope. The results show that the optimal heat treatment process of the steel is 1200 ℃ solid solution + aging of 720 ℃ for 2 h, hardness of 46 HRC, impact strength of transverse unnotched impact specimen of 150 J; good thermal stability, heat preservation at 700 ℃ for 20 h , The hardness is basically unchanged, and the hardness is above 44 HRC after heat preservation at 780 ℃ for 20 h. The precipitated phase in steel is mainly V (C, N), the precipitated phase accounts for about 4% of the total amount in the aged state, and the precipitated phase Size is 10 ~ 20 nm.