Corrosion Resistance of WE43 Mg Alloy Coated by Hydroxyapatite Film in Simulated Body Fluid

Two-layer hydroxyapatite film was prepared on WE43 magnesium alloy surface by electrochemical deposition method. XRD results showed that the film consisted of flake-like CaHPO4·2H2O and spindle hydroxyapatite after pretreatment, and the film consisted of spindle hydroxyapatite and Ca(OH)2 after hot dip process. Polarization curves showed that the compact hydroxyapatite film could improve the corrosion resistance of WE43 magnesium alloy significantly when immered in simulated body fluid (SBF). Ca(OH)2 was generated due to the relatively high concentration of hot 0.5 mol/L NaOH in the solution.