A ceramizable adhesive with high temperature resistance at 1400°C: Bonding strength and bonding mechanism

In this study, two types of high-temperature adhesives were prepared using molybdenum-modified phenolic resin (MoPF) as the matrix and TiB2 or TiB2/ZrSi2 particles as active fillers for bonding Al2O3 ceramic substrates. Shear strength testing, thermo gravimetric analysis (TGA), scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) were employed to investigate the bonding properties, thermal properties, microstructure, compositional evolution, and bonding mechanism of the adhesives. The results demonstrate that MoPF-TiB2/ZrSi2 adhesive exhibits superior bonding properties than MoPF-TiB2 adhesive. It is noteworthy that the incorporation of ZrSi2 can mitigate the internal stress induced by rapid volume expansion of the adhesive, and ensuring high density and mechanical strength through the generation of ZrB2 and ZrTiO4, which effectively prevents the sudden decline in bonding performance beyond 1200℃. The mechanical strength of the adhesive can still be maintained at 31.5 MPa after treatment at 1400℃.