The Effect of Electrolyte Concentration on Micro Arc Oxidation Coatings on Medicinal Titanium Alloy

摘要

In order to achieve the prepared functional coatings containing a predetermined ratio of calcium and phosphorus (Ca/P), and guide the rational allocation of chemical reagents, on the medicinal TC4 titanium alloy surface, the calcium and phosphorus biocoating were fabricated by micro arc oxidation (MAO) process. The coating morphology and elemental composition were observed by scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS). Besides the wear resistant test on the coating surface was executed. The influence rules of different concentrations and different molar ratio of electrolyte on the calcium and phosphorus content of medical TC4 alloy coating on micro arc oxidation system were researched, and the effects of electrolyte concentration on the molar ratio of calcium and phosphorus in the coating were also studied. The experimental results show that, with the increase of the electrolyte concentration, calcium and phosphorus content in the coating are all decreased, but the ratio of calcium and phosphorus in the coating increase, as well as the concentration of Ca/P molar ratio, and calcium and phosphorus content in coating get all lower. Wear resistant test shows that proper electrolyte concentration is helpful to improve the surface properties of coating. So if it wants to prepared one biocoating of certain Ca/P molar ratio, this certain ratio can determine the different electrolyte concentrations of Ca/P molar ratio, at last roughly determine the ratio of the compound reagent.