The preparation and mechanical properties of carbon/carbon composite joints using Ti-Si-SiC-C filler as interlayer

Carbon/carbon (C/C) composite joints were successfully prepared using Ti-SiC-Si-C compound as filler by vacuum hot-press technique. The effects of interlayer thickness and SiC transition layer on the mechanical properties of C/C joints were studied. Shear test results revealed that the joints with ~160 μm thick interlayer had the maximum shear strength (38.09±5.09. MPa), in which dense interlayer, strong interface bonding and 'nail effect' were responsible for the excellent mechanical properties of joints. Furthermore, the joints had high strength retention at no more than 1200 °C. The joints using SiC coating as a transition layer indicated lower shear strength (22.64±2.61. MPa), and those joints primarily fractured in SiC transition layer and the interface region between SiC layer and core interlayer due to the relatively loose SiC coating.