A suspension of nano-particles, with agglomerates, is injected into plasma jets. Suspension is the only way to inject such small particles with the suitable momentum. in APS, these particles would require carrier gas flow rates as high as 50 slm, which hugely perturb the plasma jet. The result is a fragmentation of the plasma droplets containing solid particles. After evaporation, the solid particles are melted and projected onto a prepared substrate
The SPS method presents the following advantages:
– the control of the coating porosity by adjusting the experimental parameters
– it enables multi-layer deposition gradient properties (composition, porosity…) using one or more suspensions
– working in embiant air with minor modifications of conventional plasma spraying system