Abstract: The microstructure, strength and hardness of martensitic precipitation hardening stainless steel 05Cr17Ni4Cu4Nb solid solution at 1 040 °C and aged at 480 ~ 620 °C for 5 h have been tested and studied. The results show that with the increasing aging temperature, the descomposition of martensitic matrix structrue gradually and the precipitation of carbide decrease. During the aging treatment, with increasing aging temperature the copper-rich phase is precipitaed as a sphere at first and then gradually developed to oval and rod shape, the size of precipitates are increased, the number decreased and the coherent interface with the matrix disappears, the stengthening effect decreases. With solution-treated at 1 040 °Cand aged at 480 °C for 5 h, the HRC hardness number of 05Crl7Ni4Cu4Nb steel is 44.3, to meet the requirement of product HRC hardness number 43.

摘要： 试验研究了 1040 ℃固溶的马氏体沉淀硬化不锈钢05Cr17Ni4Cu4Nb在480~620 ℃时效5 h的组织，强度和硬度。结果表明，随时效温度升高，马氏体基体逐渐分解,碳化物析岀而降低;在时效处理过程中，随时效温度升高，富Cu相最初以球形析出，逐渐发展成椭圆形及杆状，尺寸增大，与基体共格界面消失，强化效果减弱；05Cr17Ni4Cu4Nb钢经1040 °C固溶,480 °C 5h时效后，其HRC硬度值44.3,满足钢材HRC硬度值43的要求。

关键词: 沉淀硬化马氏体不锈钢05Crl7Ni4Cu4Nb, 时效处理, 富Cu相, 析出相