Joining ceramics using preceramic polymers

Since the last couple of years, an increasing number of publications have been appearing dealing with the use of preceramic polymers for joining mainly silicon carbide ceramics. In this paper, data concerning the joining of Al2O3, Si3N4 and C/C-f composite materials using a silicone resin or polycarbosilane are reported. Joint strength was not high in all the tested systems; the best results were obtained in the case of alumina. SEM investigations showed that the failure mechanism was mixed (cohesive adhesive) in the case of alumina and mainly cohesive in the case of silicon nitride. The joining material, a silicon oxycarbide glass, was inert towards the ceramics used, and it acted as an inorganic adhesive (adhesive bonding).