LIU Liqun, ZHOU Zehua, WANG Zehua, JIANG Shaoqun,  DING Ying

(College of Mechanics and Materials, Hohai University, Nanjing Jiangsu 210098, China)

Abstract:The researches of laser remelted plasma spraying coatings are reviewed and their future prospects predicted. Laser remelting can change a coating's microstructure fundamentally. The sprayed laminar structure changes into that of crystallized pillars. The compactness of the coating is improved, and the mechanical bond between the coating and its substrate is replaced by the metallurgical bond. All of these changes lead to the improved resistance to thermal fatigue, corrosion, wear and elevated temperature oxidation. The problems, such as cracks and coating spallation occurring after laser remelting are pointed out and their reasons are discussed. Finally, future directions of researches on laser remelted plasma spraying coatings are proposed.

Key words:laser remelting; plasma sprayed coatings; structure; characteristics