Study on novel Ag-Cu-Zn-Sn brazing filler metal bearing Ga

Novel Ag-Cu-Zn-Sn-Ga brazing filler metals were used for brazing brass and 304 stainless steel. The influence of various content of Ga on the mechanical properties and microstructure of novel Ag-Cu-Zn-Sn filler metals was investigated in this paper. The results shown that wettability, oxidation resistance and mechanical property of Ag-Cu-Zn-Sn filler metals were improved significantly with addition of Ga. In addition, wetting ring was found on the front edge of the melted brazing alloy which consisted with silver-based solid solution, copper-based solid solution. Moreover, the 17AgCuZnSn-xGa filler metals displayed finer and more uniform microstructures when appropriate Ga was added, which gamma-Cu5Zn8 was disappeared when Ga content was at about 2 wt%. The results also indicated that the shear strength of the joints of brass/stainless steel brazed with 17AgCuZnSn-2Ga filler metal was 36.9% higher than the shear strength of the 17AgCuZnSn filler metal, which presented that the addition of Ga not only can improve the wetting property, but also can enhance mechanical properties of the brazing joint. (C) 2016 Elsevier B.V. All rights reserved.