The effects of gas and metal characteristics on sprayed metal coatings

Supersonic particle deposition (also known as cold spray) is a surface coating process whereby metal particles are accelerated to supersonic speeds while entrained in nozzle gas flow and are subsequently deposited by impact onto a surface. Particle velocity is critical for optimal deposition efficiency and coating quality, and several parameters, including gas conditions, particle characteristics and nozzle geometry affect particle velocity. This study investigates the relationship between particle velocity and coating quality and investigates how nozzle design influences particle velocity. Performance is described through modelling and verified by direct velocity measurements.