Brazing dissimilar materials with rapidly solidified filler metals STEMET

Rapidly solidified filler metal alloys STEMET registered are being used to join different metals, as an example, plasma-facing components (PFCs) for fusion reactor first wall and experimental arrangements in engineering reactors (EAER). Various combinations of Cu, Ti, and Zr based metals for filler metal alloys have been developed for brazing. Techniques for brazing different metal-combinations, such as Cu-Be, Cu-W, C-V, C-Mo, stainless steel-Zr, Ti, Cu are given. Samples were investigated by metallographic, X-ray studies, and other technique. Specimen brazed joints of Be and a CuCrZr alloy have sustained 1000 heating cycles at power density of 11 MW/m2, and also single heating before the flash-off of the Be of 13 MW/m2 without fracture. The mock-up of ternary joint W-Cu-CuCrZr alloy has withstood 900 thermo- cycles at power density of 15 MW/m2 without tiling and brazed zone damage. Prototypes of SS-Zr brazed with STEMET registered based on zirconium joints have remained tightness at temperature 650 C and pressure difference up to 6 MPa. STEMET registered based on titanium was used for manufacture of adapter ''austenitic steel - titanium alloy''. These reducers were subjected temperature-cycle test and load by internal and external gas pressure. In all cases leak around the joints was not available. (orig.)