Study of alternative SS/Cu-alloy joining methods for ITER

Presented paper proposes casting, fast brazing and explosion bonding as alternative SS/Cu-alloy joining methods for the ITER. Tensile and thermal fatigue tests were used for the joint characterization. In particularly it was shown that SS/CuCrZr joint produced by casting revealed ultimate tensile strength (UTS) of about 300 MPa and about 30% elongation. Samples failed through the based CuCrZr and never through the SS/CuCrZr boundary. Metallography of the SS/Cu-alloy cross-section, its element distribution and hardness measurements are presented. Checking the applicability of above mentioned joining methods to ITER relevant conditions, a number of actively cooled mock-ups were fabricated and subjected to the thermal cycling on TSEFEY-M electron beam facility (Efremov Institute, Russia). Test conditions applied during the tests were 15 MW/m2, much higher than the ITER normal operation condition, to accelerate the thermal fatigue performance. The results of the post-mortem analysis are presented.