Quartz Fibers Reinforced SiNB Ceramic Matrix Composites Prepared by PIP

摘要

The 2.5D quartz fibers reinforced SiNB ceramic matrix composites (2.5D SiO_(2f)/SiNB) were prepared through polyborosilazane infiltration and pyrolysis (PIP) method. The SiNB ceramic precursors and their pyrolytic products were characterized and the mechanical properties, dielectric properties, micro-structures and fracture mechanism of the composites were investigated. The results of FT-IR spectra and XRD patterns show that when the pyrolytic temperature reached 900°C, the pyrolytic products are essentially inorganic. The tensile strength and the tensile modulus are 65MPa and 30GPa respectively, the tensile strength at 800°C is 35MPa,and the dielectric constant is 3.2, the dielectric loss angle is smaller than 6 × 10~(-3). And the composites are ductile fracture, whose fracture faces have distinct fibers pull-out.