Influence of Spray Angle and Carrier Gas Type on Micro Cold Spray Deposition of Cu Coatings on AlN Substrates

Abstract

Deposition onto conformal or angled surfaces not normal to the deposition nozzle is one of the primary impediments to implementing micro cold spray (MCS) as a film deposition technique for mass production. Increasing the ability for MCS techniques to effectively deposit on the complex geometries intrinsic to manufacturing requires understanding the effects changing deposition angles has on the film coherence, both within itself and to the substrate. In this study, deposition angle and MCS carrier gas composition are proposed and tested as variables that affect the MCS film morphology and coherence. Three gas compositions are each used to deposit MCS films at intervals of ten degrees from normal to the deposition nozzle down to 50°. Films were then tested for coherence and adhesion before being examined optically and through scanning electron microscopy to identify patterns among the various carrier gas-angle combinations