钼对等离子堆焊钴基合金组织结构及性能的影响

采用光学显微镜，扫描电镜（SEM），X射线衍射（XRD），透射电镜（TEM）和磨粒磨损试验，研究了8％Mo对等离子堆焊钴基合金组织结构和性能的影响。结果表明，堆焊合金层主要是由面心立方的γ（Co）和六方结构的M7C3构成，并且在钴基固溶体中存在着许多堆垛层错。8％Mo的加入，没有改变合金层的相结构，但其亚结构却发生了变化，堆垛层错消失，在钴基固溶体中出现了大量的位错。8％Mo的加入，不但可以细化钴基固溶体和共晶体组织，还可以提高合金层中富Cr碳化物相的相对含量，有助于提高合金层的硬度和耐磨性能。

Effect of Molybdenum on Microstructure and Properties of Cobalt-Based Alloy Coating Deposited by Plasma Transferred Arc Process

The effects of 8% Mo on the microstructure and properties of the cobalt-based alloy coating were investigated using optical microscope,scanning electron microscope(SEM),X-ray diffraction(XRD),transmission electron microscope(TEM),and abrasive wear test.It was found that a cobalt-based solid solution with a face-centered cubic crystal structure is presented accompanied by the secondary phase M_7C_3 with a hexagonal crystal structure in the cobalt-based alloy coating.There are lots of stacking faults existing in this coating.The addition of 8% Mo does not change the phase composition,but the substructure changes from sacking faults into dislocations.The addition of 8% Mo can refine the Co-rich dendrites and Cr-rich carbides formed in interdendritic region.The mass fraction of Cr-rich carbides slightly increases.All these results are beneficial to increasing the hardness and the wear resistance of the deposited coating.