Numerical Simulation of High Speed Molten Nickel Droplet Impacting on the Stainless Steel Substrate

The solidification and splash phenomena of Ni during plasma spray deposition were simulated by VOF model. The Navier⁃Stokes equations are solved in combination with the volume⁃of⁃fluid technique to track the free surface of the particles. In addition, the heat transfer including phase change is modeled using the enthalpy method. The coating formation process of nickel droplets at high speed was simulated by setting three different experimental conditions. The formation mechanism of nickel coating was analyzed deeply. During the spraying process of different speeds, the diffusion coefficient of higher droplet speed is greater than that of slower speed and there will be splash. In the case of different substrate temperatures, the higher the substrate temperature, the farther the molten particle tiling distance is. In addition, the diameter of the molten droplet is changed. Under the same other simulation conditions, the larger the particle diameter, the larger the spread distance, but it is not linearly related, and the larger the particle, the greater the thickness of the solidified sheet.