Corrosion Behavior and Osteogenic Activity of a Biodegradable Orthopedic Implant Mg–Si Alloy with a Gradient Structure

A gradient Mg-8 wt % Si alloy, which was composed of the agglomerated Mg2Si crystals coating (GMS8-1) and eutectic Mg–Si alloy matrix (GMS8-2), designed for biodegradable orthopedic implant materials. The bio-corrosion behavior evaluated by electrochemical measurements immersion tests. results show that a significant improvement resistance achieved using as compared with traditional (MS8), should be attributed to compact insoluble phase distributed on surface material. Especially, GMS8-1 exhibits highest polarization 1610 Ω, lowest corrosion current density 1.7 × 10−6 A·cm−2, slowest rate 0.10 mm/year. In addition, GMS8-2 better osteogenic activity than MS8, no cytotoxicity MC3T3-E1 cells. This work provides new way design Mg alloys some certain biological functions.