High heat flux test and cooling effect of tungsten brazed mockups with swirl tube

Abstract It is so important that the bonding technology between tungsten and dissimilar metals for the PFC of ITER and DEMO, KSTAR. The development of tungsten brazing technology was first launched for the KSTAR PFC. Flat type tungsten block was brazed on CuCrZr in vacuum at a temperature of 980 °C for 30 min using silver free brazing alloy. The brazing filler is a 0.05 mm thick-plate made of a Ni-Cu-Mn alloy. Tungsten brazed mock-ups with a swirl and smooth tube were tested at an electron beam facility, KoHLT-EB(Korea heat load test facility-Electron Beam) in KAERI. The high heat flux test was performed for tungsten brazed mock-ups with a swirl and smooth tube under the heat flux of about 5.4–8 MW/m 2 . The test results show there are no delamination or failures at the bonding joints during and after all the heat flux test. According to the thermal hydraulic analysis and results of heat flux test, the cooling effect of the smooth tube was better than one of the swirl tube at the conditions of the coolant of about 0.35 MPa and the heat flux of over about 5 MW/m 2 .