Effect of metal powder properties on the deposition characteristics of cold-sprayed Ti6Al4V-TiC coatings: An experimental and finite element study

Feedstock powder properties have a significant influence on the quality of cold sprayed coatings. Here in the present study, Ti6Al4V-TiC metal matrix composites (MMCs) were deposited using spherical and irregular Ti6Al4V powders manufactured using gas atomization and Armstrong processes. MMC coatings deposited using the two powders showed different coating properties in terms of ceramic retention, porosity, and deposition efficiencies. For similar initial-metal ceramic mixtures, MMCs deposited using irregular powders showed higher ceramic retentions and lower porosity. Finite element simulations demonstrated the presence of near-surface porosity and surface roughness as a key factor influencing the ceramic retention in such coatings. For MMCs deposited using irregular powders, the closure of the voids and increased compaction of the substrate led to increased substrate crater depth and impact energy dissipation, thereby promoting ceramic retention. The present work clarified that by tailoring the metal powder properties i.e. by changing their surface morphology and inducing porosity, MMCs with higher ceramic retentions can be deposited using cold spray process.

Automated summary

By adjusting the properties of metal powders, such as surface morphology and porosity, MMCs with higher ceramic retentions can be deposited using the cold spray process, affecting the quality of the coatings.