Helium release from 19-year-old palladium tritide

doi:10.1016/0022-3115(92)90499-B

Journal of Nuclear Materials

Volume 187, Issue 3, May 1992, Pages 209-214

https://doi.org/10.1016/0022-3115(92)90499-B Get rights and content

Abstract

Eleven nineteen-year-old samples of palladium deuteride-tritide originally placed under 100 kPa of tritium have been monitored for pressure during their lifetimes. A model has been constructed, which relates the pressure to the tritium and ³He concentrations inside the solid samples. Two tritide samples replenished with 2100 kPa of tritium throughout their lifetime started to copiously outgas ³He at a helium/palladium atom ratio of 0.50 to 0.55. Four other samples were originally reacted with pure tritium and never replenished. These started to outgas mainly ³He at a helium/palladium ratio of 0.36 to 0.37 at about one-eighth the rate of the replenished samples. All six samples started their outgassing at 6000 days. Two samples were made with D-T and replenished with tritium. Neither outgassed although the helium/palladium ratio is presently about 0.4. Three samples were also made with D-T and never replenished, and no outgassing was seen up to a helium/palladium ratio of 0.24. From the change in the volumes of two samples, we have calculated a helium bubble gas density of 1.8 × 10⁵mol/m³, in agreement with nuclear magnetic resonance data.

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Helium release from 19-year-old palladium tritide

Abstract

J. Nucl. Mater.

Fusion Technol.

Phys. Rev.

Phys. Rev. Lett.

Phys. Rev.

Phys. Rev.