Oxide‐Free Titanium Coatings by Wire Arc Spraying in a Silane‐Doped Inert Atmosphere

The high oxygen affinity and tendency to nitride formation in the presence of nitrogen represent a major challenge for the application of thermally sprayed titanium coatings. Thus, there are only two established thermal spraying processes to produce titanium coatings, i.e., cold gas spraying and vacuum spraying. The present study was designed to overcome previous limitations by transferring the coating process to a silane‐doped argon gas environment to obtain extremely low oxygen partial pressure (p 02 < 10 −23 Pa). With this approach, oxide‐free titanium coatings could be realized with a wire arc spraying system, which is a process that is otherwise unsuitable for the application of materials with high oxygen affinity. The coatings created are oxide‐ and nitride‐free and feature low porosity. Moreover by transferring the corundum blasting process to this environment, the native oxide film on the substrate surface is removed and its reformation suppressed. Thus, full material bonding conditions are created, resulting in extremely high adhesive tensile strengths.