Title | Improvement of Ni-Cr-Mo coating performance by laser cladding combined re-melting |
Authors | Wang, Qin-Ying Bai, Shu-Lin Zhang, Yang-Fei Liu, Zong-De |
Affiliation | Peking Univ, Coll Engn, Ctr Appl Phys & Technol, Dept Mat Sci & Engn,HEDPS,LTCS, Beijing 100871, Peoples R China. North China Elect Power Univ, Minist Educ, Key Lab Condit Monitoring & Control Power Plant E, Beijing 102206, Peoples R China. |
Keywords | Ni-Cr-Mo alloy coating Laser re-melting Defect evolution Hardness Corrosion resistance CHROMIUM-OXIDE COATINGS THERMAL SPRAY COATINGS MECHANICAL-PROPERTIES CORROSION BEHAVIOR PITTING CORROSION ALLOY COATINGS MICROSTRUCTURE RESISTANCE HVOF POSTTREATMENT |
Issue Date | 2014 |
Publisher | 应用表面科学 |
Citation | APPLIED SURFACE SCIENCE.2014,308,285-292. |
Abstract | Although being an efficient technique to produce metallic alloy coating, laser cladding may leave original unmelted particles in the coating. Further treatment is thus necessary to improve the coating quality, and laser re-melting therefore becomes a potential method. In this study, Ni-Cr-Mo alloy coatings were prepared on Q235 steel substrate by laser cladding (coating N1) and then re-melted by laser (coating N2) with the same technic parameters. The initial defect evolution and its effect on hardness and corrosion resistance of coatings were studied. The results show that there are fewer and smaller defects in coating N2 than in coating N1, which is ascribbed to the disappearance and partial melting of Cr/Cr2O3 particles. The nearly unchanged hardness of coatings N1 and N2 is justified by both Vickers tests and nanoindentation combined theoretical calculation. Coating N2 with higher positive corrosion potential and lower corrosion current density exhibits better corrosion resistance than coating N1. Above results prove that laser re-melting can refine the microstructure and improve corrosion resistance of coatings to some degree. (C) 2014 Elsevier B.V. All rights reserved. |
URI | http://hdl.handle.net/20.500.11897/154244 |
ISSN | 0169-4332 |
DOI | 10.1016/j.apsusc.2014.04.156 |
Indexed | SCI(E) EI |
Appears in Collections: | 工学院 |