Formation of TiO2 Thin Film on Antibacterial Metal Injection Molding Stainless Steel Orthodontic Bracket 17-4 PH Using Physical Vapor Deposition Method

This study aims to equip orthodontic bracket SS 17-4 PH fabricated using metal injection molding with antibacterial properties. This can be achieved by applying TiO2 coating on the surface of brackets using magnetron sputtering PVD method. This method is chosen due to its compatibility to be used on bulk metal and its ability to control thin-film stoichiometry. Samples were prepared using the series of following steps which comprised of metal injection molding, binder elimination with solvent and thermal debinding, sintering in vacuum and argon atmosphere, electropolishing, and magnetron sputtering PVD coatings as the final stage. Negative bias, sputtering power, and partial pressure on vacuum chamber were set as the constant parameters. The atmosphere inside the PVD chamber was controlled using oxygen and argon gases. XRD and SEM observations were carried out to obtain the information on the phase and morphology of the films. Rutile and anatase crystalline structures with 2,27 nm and 9,78 nm crystal size were measured in as-deposited PVD TiO2 respectively. The deposition films were achieved in the range of 3 μm-8 μm.