@ARTICLE{Wang_Ruoxu_Investigation_2023,
 author={Wang, Ruoxu and Liu, Lubei and Xue, Zongheng and Tan, Teng},
 volume={vol. 68},
 number={No 4},
 journal={Archives of Metallurgy and Materials},
 pages={1623-1632},
 howpublished={online},
 year={2023},
 publisher={Institute of Metallurgy and Materials Science of Polish Academy of Sciences},
 publisher={Committee of Materials Engineering and Metallurgy of Polish Academy of Sciences},
 abstract={This paper introduces an approach for vacuum brazing of niobium-316L stainless steel transition joints for application in superconducting radiofrequency cavity helium jackets. The study takes advantage of good wettability of Ag-Cu-Pd brazing alloy to suppress brittle Fe-Nb intermetallic formation, hence improve the joints’ mechanical performance. The wettability of Ag-Cu-Pd filler metal on niobium, the interface microstructure and mechanical properties of the transition joints were investigated. Two kinds of Ag-Cu-Pd filler metals had been studied and wet well on the niobium, and the wettability of Ag-31.5Cu-10Pd filler metal on niobium was better than Ag-28Cu-20Pd filler metal. Microstructure characterization demonstrated the absence of brittle intermetallic layers in all of the joint interfaces. Mechanical properties of samples prepared with Ag-31.5Cu-10Pd filler metal were also better than their peers made with Ag-28Cu-20Pd filler metal both room temperature (300 K) and liquid nitrogen temperature (77 K). The transition joints displayed shear strengths of 356-375 MPa at 300 K and 440-457 MPa at 77 K, respectively. After undergoing ten thermal cycles between the room temperature and the liquid nitrogen temperature, the transition joints’ leak rates were all lower than 1.1×10 –11 mbar·L/s. Therefore, Ag-Cu-Pd filler metal is applicable to high vacuum vessels used at cryogenic temperatures.},
 type={Article},
 title={Investigation of the Microstructure and Mechanical Properties of Brazing Joints between Niobium and 316L Stainless Steel using Silver-Copper-Palladium Filler},
 URL={http://www.journals.pan.pl/Content/129671/PDF/AMM-2023-4-47-Tan.pdf},
 doi={10.24425/amm.2023.146232},
 keywords={Ag-Cu-Pd brazing alloy, niobium, vacuum brazing, 316L stainless steel, SRF cavities},
}