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The CuMn - based filler was used to brazing TZM and Kovar alloys.By means of DTA, helium mass spectrometer, laser confocal microscope, SEM and EDS,the melting point and wettability of TZM and Kovar alloys were tested and the gas tightness, microstructure, interfacial structure composition of the welds were also tested. The results show that: At 965 ℃, the wetting Angle of Cu-Mn base solder on TZM and Kovar alloy sample is 30.77 ° and 12.30 ° respectively. When the largest induced current is 430A, the solder spread out evenly on weld and the weld areas were without crack, without defects such as bubbles. The leakage rate test of welding are better thanS6×10^-11 Pa.m3/s. The middle area of the weld is CuMn metallurgical solidification organization, solder with TZM reaction interface area is relatively narrowd and with Kovar alloy interface reaction area is wider. Mn and Cu in the filler metal and Fe in Kovar alloy are more likely to diffuse and migrate to each other to form the metallurgical fusion reaction.