Formation of a thermal spray coating was studied using both numerical simulations and experiments. In the experiments, nickel particles were sprayed onto stainless steel and glass substrates using a dc plasma torch. Inflight particle temperatures were measured at the substrate using a ratio pyrometer. Particle tracking velocimetry was used to obtain particle impact velocities. The substrate was heated by an electric heater and its temperature was monitored with a thermocouple. We studied changes in splat shape as a function of substrate temperature. A 3D model of free-surface flows with heat transfer, including solidification, was used to simulate the impact of nickel particles onto the substrate The impact conditions of the particles were those of the experiments. The nickel particles were 61 mm in diameter and had a temperature of 2050DC (i.e. BOODC above the melting point) The impact velocity was 48 m/s. Fluid flow in impinging particles was modelled using a finite difference solution of the Navier-Stokes equations in a 3D Cartesian co-ordinate system. The surface profile of the deforming particles was defined using the fractional volume of fluid\" scheme. The enthalpy method was used to solve the energy equation for the liquid and so lid phases of the particles at the same. Heat transfer within the substrate was by conduction only.

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