Electrochemical behavior of Co-Cr alloy in NaCl solution

The Co-Cr alloys which have an excellent mechanical property and corrosion resistance are known as one of the most important metallic biomaterials. In this study, the electrochemical behavior of Co-Cr alloy in deaerated different electrolytes was investigated by using polarization curve measurements. Ti and stainless steels (Type 316) were used as a comparing material. The Co-Cr alloy has high corrosion resistance compared with the stainless steel in NaCl solution. The current increasing with the pitting corrosion was appeared in polarization curves of stainless steels. But it was disappeared in polarization curves of Co-Cr alloy. The passive state of the Co-Cr alloys was kept even in the pitting region of the case of stainless steels. The passive film on the Co-Cr alloy is stable as same as the film on Ti. According to the polarization behavior, the Co-Cr alloys are expected to use as the biomaterials.