Thermal-Sprayed Coatings on Bushing and Sleeve-Pipe Surfaces in Continuous Galvanizing Sinking Roller Production Line Applications

Coatings

Sihua Duan¹  Guangwei Zhang²  Deyuan Li²  Nannan Zhang²  Ning Zhang² 

[1] Dalian Huarui Heavy Industrial Special Spare Parts Co., Ltd., Dalian 116052, Liaoning, China;Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, Liaoning, China;

关键词: sink roller;    bushing;    sleeve pipe;    thermal spray;    high-velocity oxy-fuel (HVOF) spray;    welding overlay;   

DOI  :  10.3390/coatings7080113

来源: DOAJ

【 摘 要 】

This paper describes thermal spray techniques for making hard coatings on bushing and sleeve component surfaces. Specifically, plasma-arc welding was used to produce 5-mm thick Co-Cr alloy welding overlays on the bushing, while a high-velocity oxy-fuel spraying technique and laser re-melting technique were used to produce thinner coatings of Co-Cr-Ni+WC of about 1mm thickness on the sleeve-pipe counterparts. The surface-treated components were then submerged in liquid zinc to study the corrosive behaviour of the surface coating and substrate. Both the scanning electron microscope and energy dispersive spectrometer analyses were used to study the microstructure and phase composition of both coatings and substrates prior to and after corrosion experiments. The results show that the microstructure of the bushing consists of γ-cobalt solid solution as well as the eutectic structure of γ-cobalt and carbides, which have good corrosive resistance against molten zinc. Meanwhile, the microstructure of the sleeve pipe consists of a Co-Cr solid solution with various forms of carbides, which displays the combined properties of toughness with good corrosive resistance to molten zinc.

【 授权许可】

Unknown