Heat-resistant joints of Si3N4 ceramics with intermetallic compounds formed in situ

The possibility of the improvement on the heat resistance of Si3N4 ceramic joints with intermetallic compounds formed in situ was investigated. The Si 3N4 ceramics were joined with Ti/Ni/Ti multi-interlayers between 1000 and 1 150 degreesC. The effects of various parameters, which include the thicknes s of Ti and Ni foils, the pressure imposed during bonding, the bonding temp erature and the holding time, on the microstructures and the strength (both at room temperature and at high temperature) of the joints were studied. T he results indicated that the sound joints with higher strength both at roo m temperature and at elevated temperature could be acquired with intermetal lic compounds formed in situ under appropriate bonding parameters. The shea r strength at 800 degreesC could sustain about 88 MPa. (C) 2001 Kluwer Acad emic Publishers.