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Y-doped BaZrO 3 (BZY) is of the perovskite structure (ABO 3), and is promising as an electrolyte in protonic ceramic fuel cells (PCFCs). However, factors limiting its protonic conductivity have not been clarified entirely, such as the unclear site occupancy of Y. In this work, X-ray diffraction patterns were collected utilizing synchrotron radiation with an incident energy close to energy of the-2-Y K absorption edge. Therefore, precise Rietveld refinement was performed to determine the site occupancy of Y by the anomalous dispersion effect. The results revealed that for the stoichiometric sample of BaZr 0.8 Y 0.2 O 3-δ , Y only occupied the B-site. But in the Ba-deficient sample of Ba 0.9 Zr 0.8 Y 0.2 O 3-δ , two perovskite phases with different compositions were observed. In one Y-poor phase, all Y occupied the B-site, while in another greatly Y-rich and Ba-deficient phase, Y was found to occupy both A and B-sites. These results clearly indicate the tendency towards A-site occupation of Y with an increasing Ba-deficiency.

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Nanostructured intermetallics generally exhibit high strength but limited plasticity due to the covalent nature of their bonding. In this study, high-pressure torsion followed by annealing was used to produce TiAl intermetallics with two microstructural features: (i) bimodal microstructure composed of nanograins and submicrometer grains; and (ii) nanotwins. An exceptional performance, combining ultrahigh yield strength, ~2.9 GPa, and high strain to failure, ~14%, was achieved with micropillar compression tests. Twinning, dislocation slip and grain boundary sliding appear to be active under compressive stress.