将传统马氏体不锈钢9Cr18Mo和新型含氮马氏体不锈钢SV30钢进行1050℃淬火、-80℃低温冷处理和180℃回火。对比不同热处理状态下两种钢的硬度,用光学显微镜、扫描电子显微镜、X射线衍射分析了显微组织及相组成。采用原位纳米力学测试系统Triboindenter测试了SV30钢中马氏体、残留奥氏体的纳米硬度。结果表明:SV30钢淬火后硬度仅为39.8 HRC,残留奥氏体含量高达67%;经冷处理后SV30钢残留奥氏体含量略微降低,但硬度显著提高至58 HRC。与冷处理促进传统马氏体不锈钢9Cr18Mo残留奥氏体继续转变导致硬度提高不同,冷处理促进了SV30钢中马氏体相内部的弥散析出强化,而大幅度提高了硬度。 The traditional martensitic stainless steel 9Cr18Mo and the new nitrogen-containing martensitic stainless steel SV30 steel quenched at 1050 ℃, -80 ℃ cold treatment and tempering at 180 ℃. The hardness of the two steels under different heat treatment conditions was compared. The microstructure and phase composition were analyzed by optical microscope, scanning electron microscope and X-ray diffraction. The in-situ nanomechanical test system Triboindenter was used to test the nano-hardness of martensite and retained austenite in SV30 steel. The results showed that the hardness of SV30 steel was only 39.8 HRC after quenching, and the retained austenite content was as high as 67%. The retained austenite content of SV30 steel decreased slightly after cold treatment, but its hardness increased significantly to 58 HRC. In contrast to the cold treatment that promotes the further transformation of retained austenite in the conventional martensitic stainless steel 9Cr18Mo resulting in an increase in hardness, the cold treatment promotes the dispersion strengthening within the martensitic phase in the SV30 steel and substantially increases the hardness.