Understanding of spray coating adhesion through the formation of a single lamella

Simon Goutier (1) , Michel Vardelle (1) , Pierre Fauchais (1)

1 Axe 2 : procédés de traitements de surface

Plasma spraying allows melting totally or partially micrometer sized particles, which flatten in about one µs onto the substrate to build the coating by layering resulting solidified splats. The coating adhesion is essential and depends mainly on the behaviour of first lamellae in contact with the substrate. But in the plasma spray process about 108 particles/sec impact onto the substrate, and thus it is difficult to understand the role of the different spray parameters onto the coating quality. In order to get a better understanding of phenomena involved, it is necessary to study a single lamella formation. The experimental set-up is composed of a fast (50ns) two-colour pyrometer and an imaging system, comprising two fast (1 to 10 µs) CCD cameras triggered by the velocity signal of the particle in flight prior to its impact. This work is focused on alumina particles flattening onto stainless steel (304L) substrates preheated at different temperatures during different times.

Domaines: Matériaux

Simon Goutier, Michel Vardelle, Pierre Fauchais. Understanding of spray coating adhesion through the formation of a single lamella. International Thermal Spray Conference, Sep 2011, Hamburg, Germany. pp.192-198. ⟨hal-00945420⟩