1993/09/01 by Yuh Fukai Yuh Fukai, Yuh Fukai, Nobuyuki Ōkuma Nobuyuki Ōkuma +1 · 5 citations
Earth and Planetary Sciences · Materials Science · #Cold Fusion and Nuclear Reactions #Hydrogen embrittlement and corrosion behaviors in metals #Hydrogen Storage and Materials
paper · doi:10.1143/jjap.32.l1256
From in situ observation of X-ray diffraction of Ni and Pd under a high hydrogen pressure (≃5 GPa) and temperatures (≤800°C), anomalous lattice contraction of the hydride was found to occur in 2∼3 h. This contraction, amounting to ∼0.5 Å 3 per a metal atom, remained in the recovered specimen even after the hydrogen was removed by heating to 400°C, but was annealed out at 800°C. The concentration of vacancies responsible for this effect is estimated at ∼20% of metal-atom sites. Anomalous concentration dependence of the hydrogen-induced volume and enhanced diffusion of metal atoms are explained in terms of this effect.