Brazing of Si3N4 with amorphous Ti40Zr25Ni15Cu20 filler

Amorphous active brazing filler foils having a composition of Ti40Zr25Ni15Cu20 was synthesized using a melt-spinning method in a roll forging machine in argon atmosphere. Si3N4 ceramic was brazed with synthesized Ti40Zr25Ni15Cu20 amorphous foil. The effects of brazing temperature and time on joint strength and interfacial microstructure were investigated. The structure, composition and property of the brazing alloys as well as interfacial microstructure were characterized by X-ray diffraction, differential thermal analysis, scanning electro-microscopy and energy dispersive X-ray spectroscope. The results showed that joint strength first increased then decreased with the increasing brazing time and brazing temperature, which was significantly affected by reaction layer thickness. Under the same brazing conditions, the strength of joint brazed with amorphous Ti40Zr25Ni15Cu20 filler alloy was much larger than that bonded with Ti40Zr25Cu20Ni15 crystalline filler due to improved wettabilty.