POTENTIODYNAMIC POLARIZATION OF AZ31 MAGNESIUM ALLOY WITH DCPD

Potentiodynamic polarization is the main laboratory technique used for the most relevant electrochemical corrosion characteristics determination. The Mg-3Al-1Zn biodegradable alloy electrodeposited by dicalcium phosphate dihydrate (DCPD) coating was investigated in this study. The 0.9 % NaCl solution simulating human body chloride concentration environment was used as a corrosion electrolyte. Testing temperature corresponded to human body fluids temperature (37 °C). Electrodeposition of DCPD was realized in water solution of Ca(NO3)2.4H2O, NH4HPO4 and H2O2. The influence of this surface treatment on corrosion potential and corrosion current density was evaluated. Basic potentiodynamic curves, obtained from the voltamperometric tests, were analyzed by the Tafel analyses. The improvement of the short-time electrochemical behavior after the DCPD electrodeposition on tested alloy surface was reported.