Pure
iron has been verified as a promising biodegradable
metal for absorbable cardiovascular
stent usage. However, the degradation rate of pure
iron is too slow. To accelerate the degradation of the surface of pure
iron,
silver ions were implanted into pure
iron by
metal vapor vacuum
arc (MEVVA) source at an extracted voltage of 40keV. The implanted influence was up to 2×10(17)
ions/cm(2). The composition and depth profiles, corrosion behavior and biocompatibility of Ag ion implanted pure
iron were investigated. The implantation depths of Ag was around 60nm. The
element Ag existed as
Ag2O in the outermost layer, then gradually transited to
metal atoms in zero valent state with depth increase. The implantation of Ag
ions accelerated the corrosion rate of pure
iron matrix, and exhibited much more uniform corrosion behavior. For cytotoxicity assessment, the implantation of Ag
ions slightly decreased the viability of all kinds of cell lines used in these tests. The
hemolysis rate of Ag ion implanted pure
iron was lower than 2%, which was acceptable, whereas the platelet adhesion tests indicated the implantation of Ag
ions might increase the risk of
thrombosis.