钴基合金等离子转移弧喷焊组织结构和性能研究

Research on the Microstructure and Performance of Plasma Transfer Arc Spray Welded Cobalt-based Alloy

应用光学金相、扫描电镜 (SEM )、X射线衍射 (XRD)、透射电镜 (TEM )和显微硬度测试对钴基合金等离子喷焊的组织结构和显微硬度 ,以及时效过程中的物相和显微硬度变化进行了研究。结果表明 ,合金层主要是由γ(Co)和 (Cr ,Fe) 7(C ,B) 3构成。表现出亚共晶的组织形态。它在时效过程中物相发生了变化 ,并且发生了由 (Cr ,Fe) 7(C ,B) 3向Cr2 3(C ,B) 6 的转变过程 ,时效后显微硬度平均提高约 11%。研究表明 ,时效过程中新相的析出。

The microstructure and microhardness of plasma arc spray welded Cobalt-based alloy were investingated using optical metalography,scanning electron microscope(SEM),X-ray diffraction(XRD)and microhardness testing.Meanwhile,the changing of phase and microhardness of the Cobalt-based alloy layer during aging was studied.The results showed that the Cobalt-based alloy layer was made up ofγ(Co)and (Cr,Fe) 7(C,B) 3,and the hypoeutectic structure was shown at the same time.On the other hand,the phase of the alloy layer changed during aging,and (Cr,Fe) 7(C,B) 3changed into Cr 23 (C,B) 6and the microhardness of the alloy increased about 11%.Research showde that the precipitation of new phase,the changing and the accumulation of the phase during aging were the reasons for the changing of microhardness of the spray welding layer.