Study on Ceramic Composite TiB/TiB2 Coating Mechanism on Commercial Pure Titanium and Its Osteoconduction

Titanium and its alloys are used as under-load implants due to the high corrosion resistant and mechanical properties. However, they show weakness in surface and tribology behavior. In this study, the protective composite TiB/TiB2 coating mechanism towards the diffusion pack cementation method and also their osteoconduction properties have been investigated via in-vitro experience. Boriding process was performed at the different temperatures (800 and 1000 ˚C) for certain soaking time (60 min). SEM micrographs showed a gradient B concentration regard to the formation of TiB2, Ti3B4, and TiB phases. XRD analysis also confirmed the formation mechanism and indicated that boriding at 800 ˚C tends to single phase TiB, while at 1000 ˚C tends to the formation of composite TiB/TiB2 coating. In-vitro study during two weeks immersion in simulated body fluid (SBF) showed that the TiB/TiB2 coating exchanges the bio-inert titanium surface to a bio-active surface resulting in an osteoconductive material formation. SEM image of TiB/TiB2 coating after two weeks immersion revealed that bone like apatite precipitants formed a porous structure like cancellous bone tissue on the titanium surface.