High-temperature property of carbon/carbon composite joints bonded with ternary Ti–Si–C compound

Abstract

Carbon/carbon composites were joined using Ti–Si–C compound as interlayer and high-temperature shear strength and thermal shock resistance of these joints were investigated in this paper. In order to improve thermal shock resistance of the joints, a SiC transition layer was introduced between carbon/carbon substrates and interlayer. Microstructures and phase composition of the as-received joints were characterized by electron backscattered diffraction and X-ray diffraction. Mechanical strength and thermal shock resistance of the joints were measured by high-temperature shear test and thermal cycle test, respectively. The shear test results show that, with test temperature increasing from 273 K to 1673 K, shear strength of joints gradually increases to a maximum value of 46 MPa at 1473 K, then drops suddenly at higher temperature. Joints with SiC transition layer exhibit better thermal shock resistance than the ones without SiC transition layer and strength retention can be kept up to 85%, even after 30 thermal cycles from 1673 K to room temperature.