Hydrogen Recycling At Plasma Facing Materials

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.

A compendium representing the current state of the art in the modelling, simulation and physics of the interaction of hydrogen and helium with plasma facing materials in fusion reactors. This is the topic that will determine the success of the production of energy by future Tokamak reactors and it is here discussed by the world's experts. Topics covered are recycling of hydrogen isotopes; wall fuelling and wall pumping; active control of hydrogen recycling; hydrogen and helium behaviour in solids and liquid metals; and databases for recycling.

This book is a primer on the interplay between plasma and materials in a fusion reactor, so-called plasma–materials interactions (PMIs), highlighting materials and their influence on plasma through PMI. It aims to demonstrate that a plasma-facing surface (PFS) responds actively to fusion plasma and that the clarifying nature of PFS is indispensable to understanding the influence of PFS on plasma. It describes the modern insight into PMI, namely, relevant feedback to plasma performance from plasma-facing material (PFM) on changes in a material surface by plasma power load by radiation and particles, contrary to a conventional view that unilateral influence from plasma on PFM is dominant in PMI. There are many books and reviews on PMI in the context of plasma physics, that is, how plasma or plasma confinement works in PMI. By contrast, this book features a materials aspect in PMI focusing on changes caused by heat and particle load from plasma: how PFMs are changed by plasma exposure and then, accordingly, how the changed PFM interacts with plasma.

This book focuses on tritium as a fuel for fusion reactors and a next-generation energy source. Following an introduction of tritium as a hydrogen radioisotope, important issues involved in establishing safe and economical tritium fuel cycles including breeding for a fusion reactor are summarized; these include the handling of large amounts of tritium: confinement, leakage, contamination, permeation, regulation and tritium accountancy, and impacts on surrounding areas. Targeting and encouraging the students and technicians who will design and operate fusion reactors in the near future, this book offers a valuable resource on tritium science and technology.

It became clear in the early days of fusion research that the effects of the containment vessel (erosion of "impurities") degrade the overall fusion plasma performance. Progress in controlled nuclear fusion research over the last decade has led to magnetically confined plasmas that, in turn, are sufficiently powerful to damage the vessel structures over its lifetime. This book reviews current understanding and concepts to deal with this remaining critical design issue for fusion reactors. It reviews both progress and open questions, largely in terms of available and sought-after plasma-surface interaction data and atomic/molecular data related to these "plasma edge" issues.

This reference book addresses the evolution of materials for both oxygen and hydrogen transport membranes and offers strategies for their fabrication as well as their subsequent incorporation into catalytic membrane reactors. Other chapters deal with, e.g., engineering design and scale-up issues, strategies for preparation of supported thin-film membranes, or interfacial kinetic and mass transfer issues. A must for materials scientists, chemists, chemical engineers and electrochemists interested in advanced chemical processing.

This transactions volume contains 33 papers from the CREST International Symposium on SiC/SiC Composite Materials Research and Development and Its Application to Advanced Energy Systems held May 20-22, 2002 in Kyoto, Japan. Chapters include Processing for SiC/SiC Composites; Processing for SiC/SiC Composite Constituent; Characterization of Thermomechanical Performance; and Joining Technologies for Advanced Energy Applications. 373 pages.

The aim of the biennial series of symposia on Fusion Technology, organized by the European Fusion Laboratories, is the exchange of information on the design, construction and operation of fusion experiments. The coverage of the volume includes the technology aspects of fusion reactors to provide a link to the technology of new developments and form a guideline for the definition of future work. These proceedings comprise two volumes and contain both the invited lectures and contributed papers presented at the Symposium, which was attended by 556 participants from around the globe. The 312 papers in this volume, including 17 invited papers, give a broad and current overview of the progress and trends fusion technology is experiencing now, and the future for fusion devices.