A contribution to Plasma Spray deposition process modelling and simulation based on Smoothed Particle Hydrodynamics

Plasma Spray (PS) deposition processes are based on a thermal spray impinging on a surface: a flow of powder particles are heated, melted and accelerated towards a surface that must be coated. Particles impact on the solid surface, where they spread and solidify building up a thin or thick coating layer over the substrate. To obtain coatings that offer specified morphological and micro-structural characteristics, functional properties and behaviour, suitable process parameters must be selected and possibly optimized for each coating and substrate combination. Traditionally selection and optimization are done by means of complex, expensive and time consuming trial and error experimental procedures. However deposition process modelling and predictive simulation tools can reduce time and cost to select suitable process conditions and therefore contribute to the development of new coatings. In this work a Lagrangian particle technique, Smoothed Particle Hydrodynamics (SPH), is applied to PS deposition processes, to model and simulate the impact of a droplet on a substrate in order to predict the final splat shape. A PS deposition process simulation tool prototype is proposed and validated for different geometrical configurations of the substrate surface and of the thermal spray.