Joints of Al2O3/Al/Al2O3 are formed by liquid – state bonding of alumina substrates covered with thin Ti+Cr film of 380 nm thickness using an Al interlayer of 30 µm at 973 K under a vacuum of 0.2 mPa for 5 min and an applied pressure of 0.01 MPa. The bond strength of the joints is examined by a four – point bend testing at room temperature coupled with optical, scanning and transmission electron microscopy. Results show that: (i) introduction of the thin Ti+Cr film layer greatly improves the bend strength of Al2O3/Al/Al2O3 joints produced at 973 K, (ii) has positive effect on structure transformation in the interface and leads to fabrication of reliable metal-ceramic joints.
Microstructural investigations of the interface indicated that the solid solution of Al(Cr) and the precipitates of Ti-rich intermetallic phase were formed at the Al/Al2O3 interface, which influenced strengthening of these joints. Hence a conclusion can be drawn that the interface structure influences the durability increase in Al/Al2O3 joints.