GH4169 superalloy and Si₃N₄ ceramics were vacuum-brazed with AgCuTi+Cu foam composite filler. The effect of brazing temperature on the microstructure and mechanical properties of the GH4169/Si₃N₄ joint was studied. The results show that the interface microstructure of the GH4169/Si₃N₄ joint is the GH4169 superalloy/TiCu+Ti₂Ni+TiCu₂+Ag(s, s)+TiCu₄+Cu(s, s)+TiN+Ti₅Si₃/Si₃N₄ ceramics. With the increase in brazing temperature, the element diffusion between the base metal and the brazing filler intensifies, and the interfacial reaction layer thickens, which is conducive to the improvement of shear strength. At 850 °C, the maximum shear strength of the joint is 196.85 MPa. After further increases in the brazing temperature, Cu foam dissolves completely, and the Ti-Cu intermetallic compounds increase, which is harmful to the shear strength due to the increases in the brittle phase. However, when the brazing temperature reaches 910 °C, the shear strength of the brazing joint slightly increases under the combined effect of the Ti-Cu intermetallic compounds and the thickness of the reaction layer.

In this study, amorphous Cu₈₆P_7.5Sn_4.5Ni₂(wt.%) fillers were prepared using the melt spinning method with different rolling speeds. The wetting performance of these fillers on copper was assessed under different temperatures and holding times. The results indicated that the fillers obtained through the melt spinning technique exhibited lower melting temperatures than the as-cast filler. When processed at a rolling speed of 20 m/s, the amorphization of the filler was not sufficient. The higher rolling speed promoted the formation of the amorphous structure. The amorphous filler produced at 30 m/s exhibited the narrowest melting range and the lowest liquidus temperature (622 °C), which is approximately 100 °C lower than that of the as-cast filler (725 °C). Furthermore, the amorphous fillers also exhibited better wettability toward copper under the same conditions. Notably, the amorphous filler fabricated at 30 m/s demonstrated superior wettability at 750 °C for 90 s. Owing to the optimal wettability of the amorphized filler toward copper and the lower liquid temperature, the brazed copper joint achieved a shear strength of 223.2 MPa. The fracture of the four joints occurred in the base metal. In this study, we explored the brazing performance of amorphized Cu-based fillers, facilitating the solid bonding of copper at lower brazing temperatures.