Preparation and Properties of Needle-punched Woven Quartz Fiber Reinforced S1O2 Ceramic Matrix Composites

摘要

The needle-punched woven silica fiber reinforced SiC2 ceramic matrix composites were prepared by liquid phase infiltration-in-situ solidification molding process. The prepared composites have high density and good uniformity, and the mechanical properties of the composites at room temperature. Microstructure, interfacial properties and dielectric properties at room temperature were investigated, and the strengthening and toughening mechanism of acupuncture-woven quartz fiber reinforced SiO2 ceramic matrix composites was discussed. The mechanical properties at room temperature show that the tensile strength, flexural strength, compressive strength and interlaminar shear strength of the composites reach 35.6MPa, 79.0MPa, 122.0MPa, 11.9MPa, respectively. Scanning electron microscopy (SEM) and energy spectrum of the fractures of the samples (EDS) observation and analysis showed that there was no interfacial reaction between the matrix and the fiber, and the interface was suitable. The main factors that improve the mechanical properties of composite materials at room temperature are crack steering, expansion barriers, and fiber pull-out.The dielectric properties of the composite at room temperature do not change or change much under different X, Ka, and Ku conditions. As the bulk density increases, the dielectric constant of the composite increases gradually, and the loss tangent is always maintained at 10"3 orders of magnitude.