Abstract

Reaction bonded silicon carbide (RBSiC) is an important engineering ceramic because of its high strength and stability at elevated temperatures, and it is currently fabricated using reasonably cheap manufacturing processes, some of which have been used since the 1960s. However, forming complicated shapes from these materials is difficult because of their poor workability. The purpose of this work is to join the reaction-bonded SiC parts using a preceramic polymer as joint material. The manufacturing of ceramic material in the system Si-O-C from preceramic silicon containing polymers such as polysiloxanes has attained particular interest. The mixtures of preceramic polymer and filler materials, such as SiC, Si and MoSi, were used as a paste for the joining of reaction sintered SiC parts. The joining process during the annealing in Ar atmosphere at 1450°C were described. The maximum strength of the joints was 63 MPa for the specimen joined with 10 vol.% of MoSi_2 and 30 vol.% of SiC as filler materials. Fracture occurred in the joining layer. This indicates that the joining strength is limited by the strength of the joint materials.

• Keywords: RBSiC;Polymer;MoSi_2;SiC;Joining;