Tritium and Helium-3 in Metals

Hydrogen can behave as an alkaline metal or a halogen and can react with nearly all elements of the periodic table. This explains the large number of metal hydrides. Since T. Graham's first observation of the absorption of hydrogen in palladium in 1866 the behaviour of hydrogen in metals has been studied very extensively. The interest was motivated by the possible application of metal-hydrogen systems in new technologies (e.g., moderator material in nuclear fission reactors, reversible storage material for thermal energy and large amounts of hydrogen) and by the fact that metal hydrides show very exciting physical properties (e.g., superconductivity, quantum diffusion, order-disorder transitions, phase diagrams, etc.). Many of these properties have been determined for the stable hydrogen isotopes Hand D in various metals. In comparison, very little is known about the behaviour of the ra dioactive isotope tritium in metals. This book is a first attempt to summarize part of the knowledge of tritium gained in the last few years. In addition to the task of presenting the properties of tritium in metals, I have tried to compare these data with those of protium and deuterium. Furthermore, helium-3 is connected inse parably with tritium via the tritium decay. Therefore one chapter of this book is solely devoted to the curious properties of helium in metals caused mainly by its negligible solubility.

Texte du rabat

The book surveys recent results on the behaviour of tritium and its decay product helium-3 in metals. In contrast to many earlier books which discuss the properties of the stable hydrogen isotopes without mentioning tritium, this book reviews mainly the results on tritium in metals. Due to the difficulties in preparing metal tritide samples, very important quantities such as diffusivity, superconductivity, solubility, etc. have only been determined very recently. The book not only presents the measured tritium data, but also the isotopic dependency of the different physical properties by comparing H, D and T results. A further chapter is devoted to helium-3 in metals. Aspects such as helium release, generation of helium bubbles, swelling, and change of the lattice parameter upon aging are discussed. The book provides the reader with up-to-date information and deep insight into the behaviour of H, D, T and He-3 in metals. Further important topics such as tritium production, its risks, handling and discharge to the environment are also addressed.

Contenu

1. Introduction.- 1.1 Brief Historical Survey.- 1.2 Hydrogen Isotopes.- 1.3 Hydrogen in Metals.- 1.4 Helium in Metals.- 1.5 Organization of the Book.- 2. General Aspects of Tritium.- 2.1 Production of Tritium.- 2.2 Risks Associated with Tritium.- 2.3 Discharge of Tritium to the Environment.- 2.4 Tritium Handling in Future Fusion Reactors.- 2.5 Tritium Waste Handling.- 3. Preparation of Metal Tritides.- 3.1 Electrolytical Charging of Metals with Tritium.- 3.2 Breeding of Tritium in Metals.- 3.3 Tritium Charging of Metals by Means of Nuclear Reactions and Ion Implantation.- 3.4 Tritium Charging of Metals from the Gas Phase.- 3.5 Tritium Charging of Metals by Means of Metal Tritides.- 3.6 Metals Employed for Tritium Storage.- 3.7 Permeability of Tritium in Metals.- 4. Analysis of Tritium in Metals.- 4.1 Outgassing and/or Combustion.- 4.2 Gas Release Behaviour of MTr Samples.- 4.3 Tritium Induced X Rays.- 4.4 Tritium Imaging.- 4.5 Tritium Autoradiography.- 5. Properties of Protium, Deuterium and Tritium in Selected Metals.- 5.1 Solubility of Protium, Deuterium and Tritium in Palladium.- 5.2 Solubility of Protium, Deuterium and Tritium in Palladium Silver Alloys.- 5.3 Solubility of Protium, Deuterium and Tritium in Lithium and Yttrium.- 5.4 Solubility of Protium and Deuterium in Vanadium.- 5.5 Isotope Dependence of the Phase Boundaries in the Pd-X, V-X and Nb-X (X = H, D, T) Systems.- 5.6 Optical Vibrations of Protium, Deuterium and Tritium in Niobium.- 5.7 Superconductivity of the Pd-H, Pd-D and Pd-T Systems.- 5.8 Isotope Dependence of Phonon Dispersion Curves in PdD0.63 and PdT0.7.- 5.9 Isotope Effect in Dingle Temperatures and Extremal Cross Sections of the Fermi Surface in PdHr, PdDr and PdTr.- 5.10 Diffusion of Protium, Deuterium and Tritium in Selected Metals.- 5.11 Lattice Dilation in V, Nb, and Ta Produced by Protium, Deuterium and Tritium.- 6. Properties of Helium-3 in Selected Metals.- 6.1 Basic Properties of Helium in Metals.- 6.2 Helium Release from Metal Tritides.- 6.3 He Bubbles in Metal Tritides.- 6.4 Acoustic Emission by Metal Tritides.- 6.5 Swelling of Various Metal Tritides.- 6.6 Lattice Parameter and Width of the Rocking Curves of TaTr0-cHec Samples in the ? Phase.- 6.7 Preliminary Results for Helium-3-Induced Effects in Selected Metals.- 7. Conclusion and Outlook.- References.