Influence of Initial Orientation and MAO Coating on SCC Susceptibility of Magnesium Alloy in Simulated Body Fluid with Acid Environments

Degradable magnesium alloys are promising as a medical implant device. The rolled or extruded magnesium alloy has a strong anisotropy, and its poor corrosion resistance limits its medical applications. Samples of different orientations (TD and ND60) were prepared using rolled AZ 80 magnesium alloy plates. The coating was prepared on the surface of ND60 samples by micro-arc oxidation . Slow strain rate tensile tests were performed at the 5.3 × 10^-7 s^-1 rate in air and acidic simulated body fluids, respectively. The stress corrosion sensitivity of different samples in acidic environment was investigated. Combined with the results of microscopic test, the influence of texture and coating on stress corrosion sensitivity is discussed.