*Article* **Effects of the Rare Earth Y on the Structural and Tensile Properties of Mg-based Alloy: A First-Principles Study**

**Yan Gao 1,\*, Chuang Wu 1, Wenjiang Feng 2, Yan He 2, Haisheng He 1, Jingyu Yang <sup>1</sup> and Xiuyan Chen <sup>2</sup>**


**Abstract:** In order to investigate the effect of the rare earth element Y on the strengthening potency of magnesium alloys and its strengthening mechanism under tension. In this paper, the solid solution structures with Y atom content of 1.8 at.% and 3.7 at.% were built, respectively, and their cohesive energies and stress-strain curve were calculated in the strain range of 0–20%. The calculation results of the cohesive energies showed that the structure of element Y is more stable with the increase of strains. The calculation results of stress and strain showed that Y element can improve the yield strength and tensile strength of the Mg-based alloy, and the strengthening effect is better when the Y content is 3.7 at.%.

**Keywords:** Mg-based alloy; first principles; structural properties; tensile properties
