TANTALUM COATINGS FOR INERTIAL CONFINEMENT FUSION DRY WALL DESIGNS

The coating on a dry first wall inertial confinement fusion reactor mu st survive the target explosion and be ductile, inexpensive, and compa tible with the materials in the target, i.e. have a high atomic number Z. Calculations indicate that tantalum is the best choice for the coa ting material. As a test of this design 1 mm tantalum coatings were pl asma sprayed onto ferrite steel tubes. They were then subjected to 100 heating-cooling cycles which simulated the stressful thermal cycling which would be encountered during five years of plant startups and shu tdowns. The coatings were undamaged and continued to bond well to the steel. Furthermore, chemical reactions should not degrade tantalum coa tings.