HIGHLY ADHESIVE HYDROXYAPATITE COATINGS ON TITANIUM-ALLOY FORMED BY ION-BEAM-ASSISTED DEPOSITION

A compact crystalline hydroxyapatite coating on Ti-6Al-4V substrate wi th an atomic intermixed coating/substrate interface about 27 nm in wid th was synthesized by ion beam assisted deposition (IBAD) and a follow ing post-treatment. The coating after post-treatment was identified by X-ray diffraction as crystalline hydroxyapatite. The interface betwee n coatings and substrates was studied by Auger electron spectroscopy. The adhesive strength between coatings and substrates was measured by scratch tester. The results showed that the adhesive strength of IBAD coatings is nearly twice that of ion beam sputtered coatings. The stud y also showed that coatings prepared by IBAD eliminated the interfacia l deficiencies existing in plasma-sprayed coatings.