Structure and erosion resistance of Ni60A/SiC coatting by laser cladding
(MOE Key Laboratory of Mechanical Manufacture and Automation, Institute of Material and Surface Engineering,
Zhejiang University of Technology, Hangzhou 310014, China)
Zhejiang University of Technology, Hangzhou 310014, China)
Abstract: The Ni60A and Ni60A/SiC coatings were obtained by laser cladding on 0.45% C steel. The microstructure and hardness of the coatings were studied by SEM and XRD. The erosion resistances of Ni60A and Ni60A/SiC coatings were also investigated. The results show that the structure of different coatings is up to the temperature gradient and solidifying velocity in metal-melting region during laser cladding process. The coatings consist of a cladding layer, in which dendritic crystal and bulky cell-like crystal exist mainly, and a thermo-affected layer. Ni60A/SiC coating has higher microhardness than that of Ni60A coating, which is mainly caused by SiC and complicated phases formed by Ni, Cr, Fe, C and Si. It is obvious from the erosion test that the Ni60A/SiC coating has high erosion resistance.
Key words: laser cladding; Ni60A; SiC; erosion resistance