Data Base on the High Heat Flux Behavior of Metals and Carbon Materials for Plasma Facing Components: Experiments at the 10 Mw Neutral Beam Injection Test Stand of the IPP Nagoya

摘要

Disruption events in tokamak devices are regarded as one of the main issues governing material and design considerations for in-vessel components. During disruptions heat loads in the order of 100 to 5000 MW/sq m for durations of about 100 microseconds to several tens of microseconds can cause severe damage to plasma facing components and may possibly lead to their failure. To determine the response of materials to high heat fluxes, an experimental program was carried out on metals and carbon materials using the 10 MW Neutral Beam Injection Test Stand of the IPP Nagoya. Stainless steel, aluminum, copper, and molybdenum samples, 13 grades of fine grain graphites, and pyrolytic carbon samples were subjected to hydrogen beam exposure with power densities of 15 to 120 MW/sq m and pulse durations of 50 to 950 ms. Resulting damage and threshold values for the occurrence of damage were determined and documented. Main damage observed on samples includes melting, erosion, and crack formation. The high heat flux resistance of each material tested is compared comprehensively with that of the others. Processes leading to material damage are discussed. in the case of damage on graphite, models of erosion and cracking processes are given. The implication of the experimental results for material selection and design of first wall components under the high heat flux aspect is discussed.