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A hot isostatic pressing technique was used to prepare bulk polycrystalline samples of the hydrogen-absorbing materials LaAlxNi5−x. Ultrasonic methods were used to measure the elastic moduli of these alloys. Small corrections were made for porosity so that values expected for the theoretical density were found. The various moduli decrease somewhat with increasing x; the porosity-corrected bulk and shear moduli are 137.4 GPa and 59.2 GPa, respectively, at x=0 and decrease to 126.6 GPa and 54.1 GPa, respectively, at x=1. Poisson’s ratio is independent of x within experimental error at 0.31, a value typical for metals. Debye temperatures calculated from the porosity-corrected elastic constants ranged from 360 to 365 K, and were in good agreement with those reported from heat capacity measurements. The present measurements on LaAlxNi5−x were combined with earlier heat capacity measurements of the hydrides, LaAlxNi5−xHy, to estimate the elastic moduli of the latter materials. The estimated hydride moduli were substantially lower than those of the hydrogen-free metal. These estimated moduli were used to calculate the elastic energy associated with coherent, ellipsoidal hydride precipitates. The minimum elastic energy was found for low aspect ratio, i.e., a plate as opposed to a sphere or needle.

We report the deposition of single-phase undoped and Ca-doped CuInO2 thin films from a readily synthesized source target of Cu2In2O5—circumventing the very difficult fabrication of CuInO2 targets. X-ray diffraction shows that single-phase materials were obtained over a range of substrate temperatures and deposition pressures. p-type conductivities are measured to be ∼3×10−3S∕cm, comparable to the best films previously reported. The optical properties of the films were measured by spectroscopic ellipsometry.

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