Abstract
A perovskite suspension was air plasma sprayed (APS) with a direct current (dc) plasma jet. The process conditions including the standoff distance, plasma forming gases and their ratio influence on the perovskite deposits and splats characteristics were investigated. Particularly the molten state of particles, phases obtained, morphology and composition of splats were studied. The process consists in injecting a well dispersed stable suspension of submicrometric particles. The suspension was produced by attrition milling LaMnO3 perovskite powder (mean particle size of 0.8 µm). The plasma forming gases influences drastically the obtained phases in deposits. When the plasma gas mixture contains hydrogen the heat transfer is too high and the perovskite phase is decomposed but when the plasma forming gases is Ar/He or only Ar, just a very little quantity of perovskite is found to be decomposed in the plasma jet. With Ar/He, perovskite splats are well melted, but with argon there is a high percentage of semi-melted and non-melted particles.
