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.

Mechanism of Cu Effect on Energy Release of Al/Ni/Cu Energetic Composites

“…Cu powders with volume fractions of 5, 10, 15, and 20% were added to the mixed powder of Al and Ni mix again. Al/Ni/Cu composites were prepared by mature cold spraying technology …”

“…Al/Ni/Cu composites were prepared by mature cold spraying technology. 28 The microstructures of the Al/Ni/Cu composites were investigated through Gemini SEM 300 thermal field emission equipped with an energy dispersive spectroscopy (EDS) detector. The phase structure of the Al/Ni/Cu composites were identified through X-ray diffractometry(XRD, Shimadzu 7000) with the scan rate of 4°/min from 20 to 100°.…”