Mechanochemical study of a novel Magnesium alloy with trace addition of Gd, Nd, Ce, and La rare-earth and Sr elements

Mg-Zn-Ca-Mn materials micro-alloyed by Gd, Nd, Ce, and La rare-earth and Sr alkaline elements were developed. Optical and scanning electron microscopy, X-ray diffraction spectroscopy, tensile test, immersion, and electrochemical tests were applied to analyze microstructure, mechanical properties, and corrosion behavior. While the development of the equiaxed grain structures were observed in all the alloys, the Gd-containing alloy showed the smallest grain size and lowest fraction of second phases, which resulted in the highest yield and ultimate tensile strength of 310.0 ± 14.1 and 370.4 ± 41.6 MPa, respectively. Moreover, the corrosion studies also indicated the lowest rates in the Gd, and Nd-containing alloys, with the rates of 3.6 ± 2.5 and 3.9 ± 0.2 mm/y, respectively. The mechanisms of microstructure evolution, strengthening and corrosion behavior were discussed.