The interdiffusion of these oxides to form magnesiowüstite solid solutions was investigated by means of high-temperature X-ray diffraction. The oxide mixture was annealed at the desired temperatures, and shifts in the X-ray diffraction peaks were monitored as a function of time at temperatures ranging from 1323 to 1523K. The diffusion coefficients were deduced from the X-ray data by using a mathematical model. Diffusion couple experiments were also carried out at temperatures ranging from 1473 to 1573K in order to confirm the results of the X-ray diffraction studies. A comparison of the results of the 2 types of experiment showed that the high-temperature X-ray method could be used for the study of interdissolution phenomena and thus obtain reliable data. The interdiffusivities were explained in terms of cationic migration mechanisms in the oxide matrix.

A.Jakobsson: Zeitschrift für Metallkunde, 1996, 87[1], 55-60