Interface microstructure analysis of SiO₂ glass ceramic and Ti-6Al-4V alloy joint brazed with Ti-Zr-Ni-Cu alloy

In the present paper, SiO₂ glass ceramic was joined to Ti-6Al-4V alloy with 35Ti-35Zr-10Ni-15Cu (wt-%) filler foil. The whole brazing process was performed under vacuum circumstances at different temperatures (850-1000°C) for several holding times (1-30 min). According to results of scanning electron microscopy, energy dispersive spectrometry, electron probe X-ray microanalysis and X-ray diffraction analysis, the reaction products of the interface are Ti₂O, Zr₃Si₂, Ti ₅Si₃, Ti based solid solution and Ti₂(Cu,Ni). There is residual TiZrNiCu braze alloy on the SiO₂ glass ceramic/Ti-6Al-4V alloy interface after brazing. Besides, the interface evolution model of the joint was described by four stages: diffusion and solution among atoms, formation of reaction products, precipitation and growth of reaction layers respectively.