Improvement of Microstructure and Properties of Cu Coatings Prepared with Cold Spraying by Plasma Heating

Abstract

To improve the microstructure and properties of Cu coating prepared by cold spraying, the plasma heating is used during the cold spraying process. The models of Cu particles deposited on a Cu substrate during cold spraying process without/with plasma heating are established and calculated, and the results are compared. The calculated results show that the plasma heating causes copper particles and substrates to produce greater plastic deformation during deposition. The microstructure of Cu coating prepared by cold spraying with plasma heating is experimentally investigated. Plasma heating can effectively reduce the porosity of the copper coating, improve the binding between the coating and the substrate, and reduce the grain size of the coating, which is due to the greater deformation of the copper particles under plasma heating. The experimental results are consistent with the calculation results. The results of the coating immersion experiments show that the corrosion rate of the Cu coating prepared by plasma‐assisted low‐pressure cold spraying is reduced from 1.5 to 0.094 mg cm−2 h compared with the samples prepared without plasma heating under the same conditions, which is due to the reduced porosity of the coating.