Thermodynamic modeling and diffusion kinetic experiments of binary Mg-Gd and Mg-Y systems

다국어 초록 (Multilingual Abstract)

Diffusion couple experiments for the Mg-Gd and Mg-Y systems were performed with Mg single crystals to investigate the anisotropic diffusion behavior of Gd and Y in hexagonal close packed (hcp) Mg at temperatures between 703 and 803K (430 and 530<SUP>o</SUP>C). Diffusion coefficients for both Gd and Y along the basal plane of hcp Mg are approximately three times higher than those along the normal direction of the basal plane. The impurity diffusion coefficients of both Gd and Y in hcp Mg are lower than the self-diffusion of Mg and impurity diffusions of Al and Zn by about one order of magnitude. Growth constants and inter-diffusion coefficients of the intermediate phases for both systems were determined. Accurate thermodynamic modeling of the Mg-Y and Mg-Gd systems were also carried out based on the phase diagram data obtained from the present diffusion couple experiments and available literature data.