Effect of charging energy on droplet diameters and properties of high-carbon steel coatings sprayed by wire explosion spraying

The purpose of this study is to investigate the effect of charging energy on droplet diameters and the properties of high-carbon steel coatings sprayed by wire explosion spraying. With different charging energies, droplets were collected when high-carbon steel wire explosion occurred, and the coatings were sprayed on aluminum alloy substrates. Droplet diameter distributions were obtained by using a Laser Particle Size Analyzer. Coatings were characterized by observing their spreading morphologies and cross sections with a Scanning Electron Microscope (SEM) and testing their thickness, surface roughness and Vickers indentation hardness. The results revealed that when the charging energy became greater, the droplet diameter would be smaller, the diameter distribution would be more concentrated, and droplets spread more efficiently on the substrate surface. In addition, as a result of droplets with a smaller diameter, the coatings became smoother and denser as the charging energy rose. However, the coating thickness and hardness diminished with the ascension of charging energy. The recommended charging energy is 7.18 kJ to achieve better high-carbon steel coating performance.