DETERMINATION OF THE DYNAMIC RESPONSE OF A NITRIDE GLASS PARTICULATE COMPOSITE

Abstract

The development of advanced ceramics for high strain rate applications has generated an interest in the measurement of the dynamical mechanical properties of these materials. Planar impact experiments were performed on a hot-pressed particulate composite of an oxynitride glass matrix with 50 wt% SiC filler. The samples contained less than 2 vol% porosity. The SiC filler powder was chemically inert in the oxynitride glass but was nevertheless completely wetted and homogeneously dispersed. Static and dynamic mechanical properties were measured for both the monolithic glass matrix and the particulate composite. Hugoniot curves were determined in the shock pressure range from 2.5 to 10 GPa using manganin gauges. The shock impedance of the composite was approximately that expected from the law of mixtures while the Hugoniot elastic limit (HEL) of the composite, 9.2 GPa, was close to that of the parent glass. On the otherhand, the toughness and bend strength of the composite greatly exceeded those of the parent glass.