Development of High-strength and Highly Corrosion-resistant Bulk Nanocrystalline Mg-Zn-Y Alloys with Long Period Stacking Ordered Phase

摘要

Highly corrosion-resistant Mg_(97.25)Zn_(0.75)Y_2 and Mg_(96.75)Zn_(0.75)Y_2Al_(0.5) (at.%) alloys have been produced by the consolidation of rapidly solidified ribbons. Rapid solidification brought about the grain refinement and an increase in the solid solubility of Zn and Y into the Mg matrix, enhancing microstructural and electrochemical homogeneity, which in turn enhanced corrosion resistance. Passivation behavior was observed in dynamic anodic polarization measurements on rapidly solidified Mg-Zn-Y-Al alloy. The addition of Al to Mg might modify the structure of surface films and improve the resistance to local breakdown of the films.