Effect of Rare-Earth Elements Y and Ce on the Microstructure and Mechanical Properties of ZK60 Alloy

Abstract

The Mg-Zn-Zr alloy ZK60 with added trace rare-earth elements Y(0.9wt%) and Ce(0.9wt%) were prepared. After hot extrusion and aging treatment, the tensile mechanical properties of the alloys were tested at room temperature. Microstructures of the alloys were investigated by optical microscope (OM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The existing form, affecting mechanisms of trace Y and Ce in alloys and the effects on the microstructures and mechanical properties of ZK60 alloy were discussed. The results showed that: trace rare-earth elements Y and Ce both had remarkable grain-refining effects on the alloys, while the grain-refining effect of Y was more significant than that of Ce. RE elements Y and Ce improved the mechanical properties of the ZK60 alloy, but the strengthening effect of Y was more remarkable. It was found that σb of Mg-Zn-Zr-Y alloy was improved by 12.6％. Addition of Ce to the ZK60 alloy led to an increase in ductility of the alloy from 15% to 17%.

Corrosion of magnesium alloys: the role of alloying

“…In relation to the aforementioned alloys (Fig. 3), there is ample information in the literature concerning the microstructures developed, [40][41][42][43][44][45][46][47] and hence our main focus herein is to present their corrosion kinetics in respect to the main microstructural constituents. Mechanical properties will not be covered herein, however, the authors note that the group of high(er) strength Mg-alloys (AE44, WE54, and ZK60) possess the presence of precipitates including Al 11 RE 3 , Al 10 RE 2 Mn 7 , Al 2 RE, 47 Mg x RE y , 44 and MgZn 2 , 48 with improved mechanical properties at the expense of reduced corrosion performance.…”