Abstract:The surface modification for SUS316L stainless steel was carried out by electroplating Rh, ion beam assisted deposition Ta₂O₅ and sol-gel-derived TiO₂. In Tyrode’s stimulated body fluid, the surface modified samples were investigated with electrochemical techniques. The results indicate that the electrochemical stability and dissolution are improved significantly after surface modification. Moreover, as to ion beam assisted deposition Ta₂O₅ and sol-gel-derived TiO₂ film, the metal’s dorbit electron holes filled up by the oxygen electrons make against the adsorption of hydrogen. Thus the cathode process, which is controlled by the hydrogen reduction, is held back. X-ray diffraction analysis of SUS316L stainless steel after surface modification reveal that each method forms the uniform and compact film on SUS316L stainless steel. These films prevent the dissolving of elements and improve passivation property of the SUS316L stainless steel.

Key words:  coronary stent; stimulated body fluid; surface modification; electrochemical behavior