7 - Bioceramic composite coatings deposited by the cold spray process

Abstract

The current study discusses a novel approach to producing biocompatible coatings that have been deposited at temperatures well below their melting point. The cold spray process was used to deposit 100wt.% titanium (Ti) and composite feedstock powders with 80wt.% titanium (Ti) and 20wt.% hydroxyapatite (HA) onto Al6061, SS316, and Ti-6Al-4V substrates with the aim of achieving well-bonded homogeneous coatings; the effect of process parameters and substrate material was investigated. Dense composite coatings were obtained with thicker coatings yielding the least amount of total porosity. The microhardness and adhesion were also investigated in order to identify optimum cold spray parameters. Bioceramic coatings successfully passed adhesion bend tests; there was no observable relationship between spray parameter and adhesion performance. Results indicate that the phase composition of the HA remained the same before and after the synthesis of coating.