Joining of SiC with Si infiltrated tape-cast TiB2–C interlayer: Effect of interlayer composition and thickness on the microstructure and mechanical properties

Tape-cast TiB2–C interlayers with different compositions and thickness were used to bond SiC ceramics via reactive Si infiltration at 1450 °C in vacuum. This method result in strong bonding of SiC bodies by the formation of a dense TiB2–SiC–Si composite interlayer. Resultant SiC joints show homogeneous phase distribution within the interlayer while heterogeneous one at the interface. The grain growth behavior of reaction formed SiC and TiB2 grains was observed and discussed in terms of the tape composition and the infiltration process. Average bending strength of SiC joints was measured to be from 360 MPa to 420 MPa and these joints usually fracture from SiC substrate.

► Si infiltrated TiB2–C tapes result in the strong bonding of SiC bodies by forming a dense TiB2–SiC–Si composite interlayer.
► Grain growth behavior of TiB2 and reaction-formed SiC within interlayer is affected by tape composition and infiltration process.
► Bending strengths of SiC joints higher than 360 MPa can be achieved using the pressureless infiltration technique.