Characterization of Cold Sprayed Copper Coatings on Al Alloy Substrate
This study reveals the successful low pressure cold spray deposition of near-uniform, defect free and dense copper coatings approximately 700-1900 µm thick, on Al alloy for electro-technical applications. The micro structural characteristics of the deposits have been studied using the combined techniques of X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS) and electron-probe micro analysis (EPMA). The coatings exhibited characteristic splat-like, layered morphologies due to the deposition of solid powder particles which appeared to have been plastically deformed on impact to the substrate. The developed coatings have a dense (in the range of 3090-5015 kg/m3)and nearly uniform microstructure, with almost uniform hardness values in the range of 120 -140 Hv, and electrical conductivity in the range of 23-30 MS/m. EDAX, XRD and EPMA results revealed that the main constituent in the coating is Cu.