Abstract:
Woven ceramic matrix composites have gradually become a popular material for improving the comprehensive performance of aero-engines. Failure mechanism analysis of materials provides important theoretical and methodological support for material/structure performance design and optimization. In this paper, the tensile tests of 2D-SiC
f/SiC composites with different woven densities were carried out at room temperature, and the mechanical behavior and damage mechanism of the woven composites were studied. The results show that: The proportional limit stress decreases gradually with the increase of the transverse fiber bundle woven density, and the longitudinal fiber bundle woven density has little effect on the proportional limit stress. When the density of longitudinal fiber is small, the tensile strength is low. With the increase of longitudinal fiber density, the tensile strength increases and tends to be stable, while the increase of transverse fiber density has a certain weakening effect on the tensile strength. According to the evolution of tensile stress/strain, the tensile process of the woven SiC
f/SiC composites can be divided into four typical stages. The stitching hole has a certain weakening effect on the tensile strength of the material, so it is necessary to eliminate the adverse effect of the stitching hole in the material preparation and post-treatment process.