Effect of heat treatment on the riveted joints of two-dimensional C/SiC composites

A kind of riveting method for 2D C/SiC composites by chemical vapor infiltration were presented and the effect of heat treatment on the riveted joints of 2D C/SiC has been investigated through X-ray tests, mechanical tests, microstructural characterization and industrial computed tomography tests. The experimental results pointed that the order of heat treatment process and riveting process is a key factor affecting the micro-structures, total numbers of delamination defects, fiber pulling out length and tensile fracture strength of 2D C/SiC riveted joints. The heat treatment process after riveting can release assembly stress and residual thermal stress, and reduce the delamination defects in riveted joints, while the heat treatment process before riveting could increase the delamination defects and enlarge the braided holes in the riveted joints. The tensile strength increased by 23.2% when the riveted joints are riveted followed with heat treatment process, and the tensile strength of riveted joints decreased by 27.1% if the two processes are reversed.