Studies on a combined reactive plasma sprayed/arc deposited duplex coating for titanium alloys

It was verified by SEM studies that the porosity of the RPS coatings was drastically reduced after the PVD deposition. A study of the various steps of the coating system production process suggested that titanium oxynitrides were primarily responsible for the filling of the pores and that their formation was triggered by the energy of the metal ionic bombardment and the presence of oxygen inside the cavities of the RPS coatings. The resultant duplex coating has excellent mechanical and adhesion properties.