X-ray Diffraction Analysis of High-Purity Cerium-Lanthanum Alloys

Recent developments in hot-stage and electron microscopy technology allow for metals and alloys to be successfully examined at temperatures up to 1000°C. This has been achieved for a number of light metals and their alloys, yielding new insights into microstructural refinement arising from grain growth and phase transformations. The application of SEM, EBSD and XRD are considered to have provided the greatest amount of useful information previously and we believe that this approach will provide insights into the poorly understood mechanisms of phase transformation and microstructure development in the heavy f-block metals and alloys, including U and Pu. We are determining the feasibility of high-temperature materials analysis of a series Ce-La alloys, as a surrogate [1]. Four samples of high-purity Ce-La alloys (1%, 3%, 5% and 10% La), together with Ce metal, have been used for a feasibility study into the implementation of hot stage XRD analysis. One major obstacle in the way of surface analysis of f-block elements is their high electropositivity and thus rapid tarnishing in air, as they react readily with O2 and H2O vapour to form surface oxides.