Simultaneously improving mechanical properties and corrosion resistance of Mg-3Gd-1Zn-0.4Zr alloy via ultrasonic surface rolling

Abstract

Controllable mechanical properties and uniform biodegradability are essential for advancing biomedical magnesium alloys from research to clinical applications. Ultrasonic surface rolling (USR) was investigated for the as-extruded Mg-3Gd-1Zn-0.4Zr (GZ31K) alloy. Microstructure, mechanical and corrosion properties of the alloy before and after USR processing were analyzed by various microscopy and testing techniques. The results show that USR forms a gradient surface deformation layer with a thickness approximately 950 μm on both sides. Compared to the untreated alloy, the yield strength increased by 36.5%, and the elongation was 33.2%; additionally. and the corrosion resistance improved, with corrosion morphologies becoming more homogeneous due to refined grains. This study demonstrates that USR effectively enhances both strength and corrosion resistance of the as-extruded GZ31K alloy, indicating significant potential for modifying biomedical magnesium alloys.