Effect of the basal plane orientation on Al and Zn diffusion in hcp Mg

• Al and Zn diffusivity was determined for various basal plane directions in Mg.
• Decrease in diffusivity follows an elliptical trend for hcp Mg crystal orientation.
• Crystal orientations were less significant on diffusivity at high temperature.
• Different solutes showed large variation on diffusivity in hcp Mg.

Diffusion couple experiments for Mg–Al and Mg–Zn systems with polycrystalline Mg were performed between 638 and 693 K (365 and 420 °C) and 553 and 593 K (280 and 320 °C), respectively, to determine the diffusion of Al and Zn in Mg crystal depending on the orientation of basal plane of hcp Mg. Solute (Al and Zn) diffusion coefficient decreases elliptically in Mg crystal from the basal plane towards normal to the basal plane.