The effect of F-75 alloy mixed with HAP on microstructure in corrosion test for biomaterial applications

Abstract

Co-Cr-Mo (ASTM: F-75) alloy is generally used because of their mechanical properties, good wear and corrosion resistance as well as biocompatibility. In order to obtain chemical similarity and interfacial bond form between implanted biomaterials and living tissue, addition of Hydroxyapatite (HAP) is required. This study has focused on a research in F-75 alloy mixed with HAP fabricated by powder metallurgy (P/M) technique. The effect of HAP addition ranging 2 to 10 wt. % of HAP on biocompatibility (corrosion resistance) was examined. To analyse the result, the reference sample (F-75 alloy without HAP) and composites are compared. All samples are immersed into 0.9% NaCl solution at 37 ûC in 6-week duration. Every interval of 48 hours, the weight loss per area is recorded. By increasing amount of HAP, it is noticed that corrosion rate is increasing except for composite with 2 wt.% of HAP which has the lowest corrosion rate among others. The possibilities of increasing corrosion rate are the formation of general attack and pitting. Besides, the formation of apatite layer can be seen as predicted.