UMCo50合金的同质及T800堆焊层组织及性能

Microstructure and Properties of Homogeneity and T800 Surfacing Layers of UMCo50 Alloy

采用钨极氩弧焊和等离子弧粉末堆焊在UMCo50母材上分别堆焊UMCo50焊丝和T800钴基合金粉末,利用X射线衍射仪、扫描电镜、显微硬度计、高温摩擦磨损试验机对UMCo50与T800堆焊层的组织、硬度、高温耐磨性、耐热腐蚀性能进行了对比研究。试验结果表明,UMCo50堆焊层由α-Co和ε-Co相组成,T800堆焊层由α-Co和ε-Co和Laves相组成。与UMCo50堆焊层相比,Laves相的存在明显提高了T800堆焊层的硬度和高温耐磨性,由于T800堆焊层Cr元素含量较低,耐热腐蚀性能低于UMCo50堆焊层。

Tungsten argon arc welding and plasma arc powder surfacing were used to overlay UMCo50 wire and T800 cobalt-based alloy powder on UMCo50 base metal respectively. The microstructure, hardness, high temperature wear resistance and thermal corrosion resistance of UMCo50 and T800 surfacing layers were studied by X-ray diffraction, scanning electron microscopy, microhardness tester and high temperature friction wear testing machine. The results show that the microstructure of UMCo50 surfacing layer is composed of α-Co and ε-Co, while the T800 surfacing layer is composed ofα-Co, ε-Co and Laves phase. Compared with UMCo50 surfacing layer, the Laves phase significantly improves the hardness and high temperature wear resistance of T800 surfacing layer. The thermal corrosion resistance of T800 surfacing layer is poorer than that of UMCo50 surfacing layer for its low content of Cr element.