Dissolution and diffusion behavior of solid Mn in Mg melt

Abstract

Mn is an important alloying element that can improve the mechanical properties and corrosion resistance of magnesium alloys and it belongs to the peritectic reaction type element in Mg melt. In this study, an Mn/Mg solid–liquid diffusion couple was designed to investigate the diffusion behavior of solid Mn in Mg melt at 1023 ∼ 1073 K. The dissolution behavior of Mn in Mg is dominated by Mg elements entering Mn crystal lattice from the original Mn/Mg interface. After 2 h diffusion, the Mn concentration gradient occurs between the new solid–liquid interface and the original Mn/Mg interface, and the concentration of Mn outside the original Mn/Mg interface remains about 2 wt%. For Mn/Mg solid–liquid diffusion at 1023 K∼1073 K for 2 h, the interdiffusion coefficient is in the range from 0.1 × 10-12 to 0.8 × 10-12m2/s.