High Temperature Oxidation Kinetics of Dysprosium

The United States Department of Energy has funded research on rare earths as strategic materials. In particular, the high temperature oxidation behavior and diffusion mechanisms of dysprosium are rarely reported and not well understood. The kinetics of dysprosium oxidation has been studied in an atmosphere of 20% O ₂ and 80% N ₂ at temperatures ranging from 600 – 900 C up to 50 hours. After oxidation, the samples were mounted, sectioned, and characterized using optical, SEM, EDS, and XRD techniques. Oxide thicknesses were plotted as a function of time for each temperature. The kinetics of oxidation follows linear behavior and growth occurs via oxygen diffusion to the metal-oxide interface, as determined from an inert marker experiment. With a better understanding of the oxidation behavior and diffusion mechanisms at high temperatures, future applications of dysprosium can be better assessed.