含铜超级奥氏体不锈钢的析出行为

含Cu超级奥氏体不锈钢经1200 ℃保温2 h固溶后,在600、700、800、900、1000和1100 ℃分别进行2 h时效处理,然后采用Thermo-Calc热力学计算、SEM、EDS及TEM等方法对析出相进行研究。结果表明,所有试验钢在低温600~800 ℃时效时析出相主要为沿晶σ相,在中温900 ℃时效时析出相主要是沿晶的块状σ相和晶内圆棒状的Laves相与长针状、梭状的χ相,在高温1000 ℃时主要是沿晶块状σ相,时效温度升高到1100 ℃时无析出相;随着温度的升高,析出相尺寸增大,析出相总量先增加后减少,在900 ℃时达到峰值;Cu的增加促进了Laves相与χ相的析出。

Precipitation behavior of super austenitic stainless steel containing copper

Cu-containing super austenitic stainless steel was solution treated at 1200℃ for 2 h and aged at 600,700,800,900,1000 and 1100℃ for 2 h respectively,then the precipitated phases were studied by using Thermo-Calc,SEM,EDS and TEM.The results show that the precipitated phases at 600-800℃ are mainly intergranular σ phase,that at 1000℃ are intergranular bulkσphase,rod-shaped Laves phase,and the long needle-like and fusiform χ phase,while that at 1100℃ no precipitation.As the temperature rises,the size of the precipitates increases,the total amount of precipitates first increases then decreases and reaches its peak value at 900℃,and the precipitation of Laves and χ phases is promoted with the increase of Cu content.