Effect of Y Contents on the Microstructure, Mechanical Properties, and Corrosion Behavior of Biomedical Mg–0.5Zn Alloy

Abstract

The effects of Y contents on the microstructure, mechanical properties, and corrosion resistance of biomedical Mg‐0.5Zn alloy were investigated. Results showed that an increase in Y content led to a growth in the amount of the second phase and a decrease in the spacing of the secondary dendrite arms. Additionally, the second phase changed from a uniformly dispersed point‐like shape to a semi‐continuous reticular distribution. Meanwhile, the addition of Y obviously reduced the dendritic organization and this contributed to the improvement of mechanical properties. The corrosion resistance of the alloys increased first when Y content was 2 wt.% at most, and then decreased in Mg‐3Y‐0.5Zn alloy. The gradual improvement of corrosion resistance in Mg‐1Y‐0.5Zn and Mg‐2Y‐0.5Zn was closely related to the formation of the compact corrosion layer including Y element, while the sudden drop corrosion resistance of Mg‐3Y‐0.5Zn alloy was mainly attributed to the presence of a great deal of semi‐continuous LPSO and its excessive negative potential compared with Mg matrix, which led to a severe pitting.This article is protected by copyright. All rights reserved.