New insights on the high-corrosion resistance of UHP Mg-Ge alloys tested in a simulated physiological environment

UHP Mg-Ge alloys was recently found to provide excellent corrosion resistance. This paper provides new insights on the mechanism of improved corrosion resistance of UHP Mg-Ge alloys in Hanks' solution. The studied UHP Mg-0.5Ge and UHP Mg-1Ge alloys showed superior corrosion resistance compared to UHP Mg and WE43, with the Mg-1Ge exhibiting the best corrosion performance. The exceptional corrosion resistance of the UHP alloy is attributed to (i) Mg2Ge's ability to suppress cathodic kinetics, (ii) Ge's capability to accelerate the formation of a highly passive layer, and the (iii) low amounts of corrosion-accelerating impurities.