Study of the Anti-corrosion and Anti-fretting Properties of Surfi cial Treated magnesium Alloy Bone Plate

The weakening of mechanical properties caused by rapid degradation has been an impediment to the clinical application of magnesium alloy for a long time. In this paper, the effect of surface treatment on the anti-corrosion and anti-fretting properties of magnesium alloy ZK60 was studied. Firstly, an oxidizing layer whose outer layer was porous was first made on the surface of magnesium alloy through micro-arc oxidation treatment (MAO). Then ahydroxyapatitecoating was fabricated by electrodeposition on the oxidizing layer to seal the porous layer. The corrosion resistance and fretting performance of them were investigated in vitro under a simulated bone-plate service condition. Polarization testing results showed that both of them can significantly enhanced the corrosion resistance of magnesium alloy and the corrosion resistance of the latter was better. The fretting testing results showed that obvious coating flaking occurred on the worn surface of the latter, and its anti-fretting properties are inferior to that of the former.