Biocompatibility of metal carbides on Fe–Al–Mn-based alloys

The biocompatibility and microstructural variation of Fe–Al–Mn (FAM)-based alloys have been investigated clearly. The ((Fe,Mn)3AlCx) carbide (κ′-carbide) and Fe0.6Mn5.4C2 carbide (κ-carbide) as well as Cr7C3 (Cr-carbide) were formed on FAM alloy, following phase transformation by heat treatment and surface functionalization. These carbides have important role in forming nanostructure and oxidation layer. Moreover, it was found that the albumin adsorbed onto the surface increased with increasing nano-metal carbides. Therefore, heat treatment and surface functionalization such as electro-discharging and anodization not only generates a nanostructural precipitates, but also converts the alloy surface into a nanostructured oxide surface, then increasing the alloy biocompatibility.