Wetting and brazing of YIG ceramics using Ag-CuO-TiO2 metal filler

The wetting and brazing of Y3Fe5O12 (YIG) ceramics with a Ag-8CuO-2TiO(2) filler was investigated for the first time. For comparison, the wettability of a Ag-10CuO filler on YIG ceramics was similarly investigated. The Ag-8CuO-2TiO(2 )filler has an equilibrium contact angle of approximately 31 degrees C on the YIG substrate at 1000 degrees C; thus, its wettability is excellent. Moreover, its wettability exceeds that of Ag-10CuO. The microstructure and the interfacial structure between the filler and the substrate were determined using scanning electron microscopy, X-ray diffraction, EPMA and transmission electron microscopy. The liquid Ag-8CuO-2TiO(2) filler can react with the YIG substrate by forming continuous Y2Ti2O7 layers with dotted CuFe2O4 and promote the wetting behavior and bonding performance. The average shear strength could exceed 30 MPa for the joints at a brazing temperature of 1000 degrees C. As rupture occurred adjacent to the seam at the ceramic side, the strengths of the interfaces were characterized via nanoindentation. The hardness of the interface with doped TiO2 exceeds that of Ag-10CuO, which is strengthened by the dotted CuFe2O4 among Y2Ti2O7 . (C) 2020 The Author(s). Published by Elsevier B.V.

Automated summary

The wetting and brazing behavior of Y3Fe5O12 (YIG) ceramics with Ag-8CuO-2TiO(2) filler was investigated and found to have excellent wettability, forming continuous Y2Ti2O7 layers. The average shear strength of the joints at 1000 degrees C could exceed 30 MPa, with the interface hardness exceeding that of Ag-10CuO.