Inconel 690合金TT处理后的析出相

 用扫描电子显微镜、透射电子显微镜和相分析研究了3种不同钛含量的Inconel 690合金经不同固溶温度+715 ℃×15 h，TT处理后的析出相。结果表明：合金经TT处理后，均有M23C6析出，并含有一定量的Ti(C，N)；钛含量为110%的合金中有γ′相析出，γ′相在晶内弥散分布；M23C6大多在晶界上析出，而且在孪晶界和晶内位错线处也均有析出，M23C6与界面一侧基体保持立方 立方的平行位向关系；钛含量增加，析出的M23C6尺寸变小，间距增大，晶界附近的铬含量明显提高，有利于改善合金的耐腐蚀性能。

Precipitated Phase of Alloy Inconel 690 After Thermal Treatment

The precipitated phases of alloy Inconel 690 after solid solution treatment at different temperatures +715 ℃×15 h thermal treatment have been studied by means of scanning electron microscope (SEM), transmission electron microscope (TEM) and phase analysis. The results showed that M23C6 carbides were precipitated after thermal treatment and some Ti(C,N) carbides existed in the alloy. γ′ phase was precipitated in the alloy which contains 110% titanium, and dispersed in matrix; Most of M23C6 carbides precipitated on grain boundaries, they are also precipitated on twin boundary and dislocation line. Carbides had a cube cube parallel orientation relationship to the matrix on one side. With the increase of the content of titanium, the size of M23C6 carbides became smaller, the distance of carbides was larger, the content of chromium near grain boundary was increased, as a result, the corrosion resistance of alloy Inconel 690 would be improved.