Effect of rare earth element yttrium on migration behavior of twin boundary in magnesium alloys: a molecular dynamics study

Abstract

The addition of rare earth (RE) elements can effectively improve the mechanical properties of Mg alloys, which is attributed to its ability to regulate the plastic deformation behavior of Mg alloys. Here, the effects of the concentration of RE element Y and temperature on the migration behavior of twin boundary (TB) in the Mg alloys are investigated by molecular dynamics simulation. The results show that Y element has a softening effect on the migration of TB and promoted TB migration in the Mg alloys. The higher concentration of Y element, the stronger the softening effect on TB migration, and also the faster the migration speed of TB. The results indicate that higher temperature is beneficial to TB migration, and the softening effect of Y element on TB migration in the Mg alloys decreases with the increase of temperature. In addition, the migration mechanism of TB in the Mg alloys is analyzed in detail. This work provides a theoretical basis for the design and preparation of high-performance Mg alloys.

Keywords

• Migration behavior
• Twin boundary
• Mg alloys
• Rare earth element
• Molecular dynamics simulation