HIGH HEAT-FLUX TESTS ON BERYLLIUM AND BERYLLIUM-COPPER JOINTS

A large test program has been set up to evaluate the performance of be ryllium as a plasma facing material for the divertor in thermonuclear fusion devices. Simulation of steady state heat loads of 5 MW m(-2) an d above on actively cooled divertor modules, and off-normal plasma con ditions with energy densities in the range 1-7 MJ m(-2), have been inv estigated. Thermal shock tests were carried out with the ITER referenc e grade S65-C and several Russian grades of beryllium. At incident ene rgies up to 7 MJ m(-2) the best erosion behaviour is observed for S65- C and for TGP-56. Steady state heating tests with actively cooled Be/C u mock-ups were performed at incident powers of up to 5.8 MW m(-2). Ai l samples investigated in these tests did not show any indications of failure. A Be/Cu mock-ups with Incusil braze was loaded in thermal fat igue up to 500 cycles al an incident power of 4.8 MW m(-2). Up to the end of the experiment no temperature increase of the surface and no in dication of failure was observed. (C) 1997 Elsevier Science S.A.