BEHAVIOR OF CARBON AND BERYLLIUM UNDER THERMOMECHANICAL LOADS

An extensive test program has been set up to evaluate the performance of beryllium, carbon materials and tungsten as plasma facing materials for the divertor in thermonuclear fusion devices. Experiments describ ed in this paper represent pre-irradiation testing being part of a com prehensive study on neutron damage of several plasma facing materials and components. Thermal shock tests were carried out with several grad es of beryllium, carbons and tungsten, at heat loads up to 5.3 MJ/m(2) . In these experiments CFC materials and tungsten show less erosion th an the beryllium grades. Best erosion behaviour of the beryllium grade s is observed for S 65-C and for TGP-56. Steady state heating tests wi th actively cooled Be/Cu samples and CFC/metal samples, respectively w ere performed at loadings up to 5.8 MW/m(2). The main objective of the se tests was the pre-selection of components to be included in a neutr on irradiation program and to determine the heat removal efficiency be fore neutron irradiation. All samples investigated in steady state hea ting tests (Be/Cu and CFC modules) did not show any indications of fai lure, and are thus qualified to be used in the forthcoming neutron irr adiation program. CFC modules however, show a strong variation of surf ace temperature due to the deviations in thermal conductivity of the C FC materials.