Flash joining of CVD-SiC coated Cf/SiC composites with a Ti interlayer

Flash joining of CVD-SiC coated C-f/SiC samples with a Ti interlayer was achieved using a Spark Plasma Sintering machine. The influence of different heating powers and discharge times were investigated. The sample flash joined at a maximum heating power of 2.2 kW (peak electric current of 370 A) within 7 s showed the highest apparent shear strength of 31.4 MPa, which corresponds to the interlaminar shear strength of the composites. A maximum joining temperature of similar to 1237 degrees C was reached during the flash joining. An extremely rapid heating rate of 9600 degrees C/min combined with a very short processing time hindered any reaction between the CVD-SiC coating and the Ti interlayer. The formation of a metallic joint (Ti based) in the absence of any detectable reaction phase is proposed as a new joining mechanism. For a conventionally joined SPS sample, the formation of titanium silicide phases inhibited the formation of a bond. (C) 2017 The Authors. Published by Elsevier Ltd.