Simulation and experimental study on cold sprayed WCu composite with high retainability of W using core-shell powder

A WCu composite coating with high W retention was fabricated by cold spraying using a novel W@Cu core-shell powder. The impact and deposition mechanism of W@Cu core-shell powder during cold spraying were investigated using finite element modeling in comparison to typical WCu satellite powder. The results revealed that the W@Cu core-shell powder shows non-local strain and dispersive residual stress in the final coating, resulting in a low rebound energy and interfacial bonding energy. As a result of employing the core-shell powder, a cold-sprayed WCu composite coating with a high W content can be prepared, and the coating has a non-pancake-like layer morphology. After optimizing the core-shell powder with a Ni transition layer, the final coating demonstrated super-high W retention (98.3 %) and decreased bulk porosity (1 %).