PRODUCTION AND PROPERTIES OF B₄C–ТiB₂ COMPOSITES WITH ISOTROPIC EUTECTIC MICROSTRUCTURE

Abstract

Directionally solidified B₄C–TiB₂ reinforced eutectic alloys were produced from green powder compacts by float zoning melting. Their mechanical properties were studied in a wide range of temperatures (25–1600 °С). It is shown that the high-temperature strength of the reinforced B₄C–TiB₂ composites hardly changes with increasing temperature and reaches about 200 MPa at 1600 °C. Mechanical grinding and subsequent electrical discharge sintering were used to produce reinforced B₄C–TiB₂ composites with a eutectic isotropic microstructure. The microstructure of the bulk-reinforced ceramic samples was examined. The developed ceramics meets the requirements imposed on heat-resistant and high-temperature creep rupture materials for reusable hypersonic aircraft.