【摘要】 采用光学显微镜、扫描电子显微镜、能谱仪和透射电子显微镜,研究了不同时效处理温度对254SMo超级奥氏体不锈钢的析出行为以及析出相对其力学性能的影响。结果表明,254SMo奥氏体不锈钢中的χ相呈颗粒状分布,χ相的析出敏感温度为800℃;σ相呈条状分布,析出的敏感温度为900℃。χ相和σ相均为富Mo和低Ni化合物,σ相中的Mo含量高于χ相。时效温度为900℃时,实验钢中的析出相数量最多,实验钢的抗拉强度最高,为825 MPa;延伸率最低,为31%。结合试样断口分析结果表明,相比χ相,σ相对实验钢塑性的危害更大。更多还原

【Abstract】 The effect of different aging treatment temperature on the precipitation behavior of 254 SMo super austenitic stainless steel and the effect of precipitation on its mechanical properties were studied by optical microscope(OM), scanning electron microscope(SEM) with energy dispersive spectrometer(EDS), and transmission electron microscope(TEM). The results show that the χ phase is distributed in granular form in 254 SMo austenitic stainless steel, the precipitation sensitive temperature of χ phase is 800 ℃; the σ phase is distributed in strips, and the precipitation sensitive temperature is 900 ℃. Both the χ phase and the σ phase are Mo-rich and low-Ni compounds, and the Mo content in the σ phase is higher than that in the χ phase. When the aging temperature is 900 ℃, the number of precipitated phases in the experimental steel reaches the maximum, and the tensile strength of the experimental steel is the highest, the value is 825 MPa, and the elongation is the lowest, the value is 31%. The results of the fracture analysis of the sample show that, compared to the χ phase, σ phase is more harmful to the plasticity of the experimental steel.更多还原