Hydrogen Recycling at Plasma Facing Materials: Proceedings of the NATO Advanced Research Workshop, St.Petersburg, Russia, September 15-19, 1999 (NATO Science ... Mathematics, Physics and Chemistry Book 1)

One of the most important issues in the construction of future magnetic confinement fusion machines is that of the materials of which they are constructed, and one of the key points of proper material choice is the recycle of hydrogen isotopes with materials at the plasma face. Tritium machines demand high safety and economy, which in turn requires the lowest possible T inventory and smallest possible permeation through the plasma facing materials. The recycle behaviour of the in-vessel components must also be known if the plasma reaction is to predictable and controllable, and finally, the fuel cycle and plasma operating regimes may be actively controlled by special materials and methods. The book discusses both laboratory experiments exploring the basic properties of non-equilibrium hydrogen-solid systems (diffusion, absorption, boundary processes) and experimental results obtained from existing fusion machines under conditions simulating future situations to some extent. Contributions are from experts in the fields of nuclear fusion, materials science, surface science, vacuum science and technology, and solid state physics. Front Matter....Pages i-x Density control and plasma wall interaction in Tore Supra....Pages 1-8 Wall Pumping and Hydrogen Recycling in TEXTOR 94....Pages 9-15 Hydrogen Recycling in the RFX Reversed Field Pinch....Pages 17-23 Active Control of Hydrogen Recycling by the Permeation and Absorption Techniques....Pages 25-34 Deuterium Pumping with Superpermeable Membrane in the Divertor of JFT-2M Tokamak....Pages 35-40 Wall Pumping in Tokamak with Lithium....Pages 41-49 Reflection and Adsorption of Hydrogen Atoms and Molecules on Graphite and Tungsten....Pages 51-58 Detached Recombining Plasmas in Relation to Volumetric Hydrogen Recycle....Pages 59-65 Hα spectroscopic study of hydrogen behavior in a low temperature plasma....Pages 67-73 Metal Surface Microrelief Formed Due to Sputtering By Mono- and Variable Energy Ions of Hydrogen Plasma....Pages 75-81 Recycled Hydrogen In Excited State....Pages 83-94 Main Research Results in Hydrogen Thermo-Sorptive Activation by Metal Hydrides....Pages 95-107 The Modulated Permeation Technique Used at the Open University....Pages 109-117 A Model For Calculation of Tritium Accumulation and Leakage in Plasma Facing Sandwich Structures....Pages 119-124 Transport of Hydrogen Through Amorphous Alloy....Pages 125-131 An Interaction of Hydrogen Isotopes With Austenitic Cr — Ni Steels Without and During Reactor Irradiation....Pages 133-138 Diffusion of Tritium In V, Nb and Ta Under Concentration, Temperature and Electric Potential Gradients....Pages 139-145 Deuterium Superpermeation Through Niobium Membrane....Pages 147-155 Effects of Helium On The Superpermeation of the Group va Metals....Pages 157-165 Membrane Bias Effects On Plasma Driven Permeation of Hydrogen Through Niobium Membrane....Pages 167-175 Plasma Driven Permeation Through the Nb Membrane at Low Temperature....Pages 177-183 Phenomenology Model of Hydrogen Evacuation by Metal Membranes....Pages 185-194 Hydrogen Recycling and Wall Equilibration In Fusion Devices....Pages 195-201 Mechanisms of tritium retention in, and the removal of tritium from plasma facing materials of the Fusion Devices....Pages 203-212 Studies on Tritium Interactions with Plasma Facing Material at the Tritium Process Laboratory Of Jaeri....Pages 213-221 Tritium Recycling and Inventory in Eroded Debris of Plasma-Facing Materials....Pages 223-237 Effects of Cu-Impurity on Retention and Thermal Release of d Implanted Into Be....Pages 239-245 Deuterium Retention In Beryllium and Beryllium Oxide....Pages 247-264 The Effect of Radiation Damage and Helium on Hydrogen Trapping in Beryllium....Pages 265-272 Atomic Hydrogen-Graphite Interaction....Pages 273-280 Deuterium Retention in si Doped Carbon Films....Pages 281-287 Retention of 100 eV Tritium in Tungsten at High Fluxes....Pages 289-299 Hydrogen Absorption and Desorption Behavior With A Boronized Wall....Pages 301-306 Out of Pile Experiments on the Investigation of Hydrogen Interaction With Reduced Activation Ferritic-Martensitic Steel F82H.....Pages 307-312 Structure and Relief Modification of Titanium and Boron Modified Graphite Under Light Ion Irradiation....Pages 313-318 The simulation of the diagnostic mirror behavior under hydrogen isotope irradiation....Pages 319-329 Surface Loss Probabilities of Neutral Hydrocarbon Radicals on Amorphous Hydrogenated Carbon Film Surfaces: Consequences For The Formation of Re-Deposited Layers in Fusion Experiments....Pages 331-337 Device for Investigations of Tritium Retention in and Permeation Through Metals and Structural Materials....Pages 339-348 Thermocycling in Gaseous Hydrogen as a way of the Hydrogen Degradation Acceleration....Pages 349-354 Back Matter....Pages 355-363