In the field of superconducting radiofrequency (SRF) cavities for the acceleration of particle beams, titanium-vessels are commonly used to house cavities made from pure niobium; the intermediate space being filled with liquid helium to cool down the cavities to 2°K to reach superconductivity. The titanium-vessel is connected to piping for vacuum pumping, liquid helium transfer and the beam line, that are usually made from stainless steel. In former designs, the material transitions from titanium to stainless steel was realized by explosion bonding which restrict compact designs and are expensive to procure and fabricate. Alternatively, brazed tubular transitions allow the application of thinwalled material and are more versatile with respect to design features. In the present work, brazed tubular transitions and cylindric mechanical test samples between pure titanium (Grade 2) and stainless steel AISI 316LN with either AgCuIn- or AgGaPd- filler metals were performed. Mechanical tests conducted at room and cryogenic temperature with a posterior metallographic analysis of the brazed interface show satisfying shear strengths above 100 MPa at both temperatures. An extensive test campaign, including thermal cycling, non-destructive testing and metallographic analysis on different actual transition geometries were successfully conducted without degradation of the joints, which qualifies these components for the use in particle accelerator technology.
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