Room and high-temperature mechanical and thermal properties of SIC fiber-reinforced SIC composite sintered under pressure

Polycarbosilane-impregnated 2D woven SiC fiber-reinforced SiC composites with 52 vol% of fibers were fabricated by hot-pressing at 1650-1750 degreesC under a pressure of 40 MPa using sintering additives of an Al2O3-Y2O3-CaO system. The composites fractured in a non-brittle manner, Maximum strength of the composites hot-pressed at 1700 degreesC or 1750 degreesC did not decrease up to a test temperature of 1200 degreesC. The fracture energy increased with increasing test temperature and peaked at 1200 degreesC. Thermal conductivity increased with increasing bulk density, and the values were 7-14 W/mK at room temperature. (C) 2000 Elsevier Science B.V. All rights reserved.