不同稀土元素添加量对K465合金微观组织与力学性能的影响

Effects of Rare-earth Elements Content on Microstructure and Mechanical Properties of K465 Superalloy

利用金相技术和扫描电镜(SEM)观察分析了稀土元素(Ce+Y)含量对K465合金微观组织的影响,并测试了合金的室温瞬时拉伸性能和高温持久性能。结果表明:(Ce+Y)含量为0.03%(质量分数,下同)的合金碳化物变质处理后形态良好,高温持久性能大幅提高;(Ce+Y)含量为0.06%的合金枝晶间区大块γ′相的边缘析出富(Ce+Y)相,从而使合金的持久性能明显下降。

The effect of （Ce＋Y） content on microstructure of K465 superalloy was examined by met- allography technique and scanning electron microscope（SEM）. The tensile properties at room temper- ature and the high temperature stress-rupture properties were tested. The results show that the mor- phology of carbides can be well modified by addition 0.03G（mass fraction） of （Ce＋Y） which induces the improvement of high temperature stress-rupture properties. The high temperature stress-rupture properties decrease due to the precipitation of rich （Ce＋Y） phases besides the large size γ＇ phases in the interdendritic area while adding 0.06G of （Ce＋Y）.