Microhardness, Friction and Wear of SiC and Si3N4 Materials as a Function of Load, Temperature and Environment.
Annual technical rept. no. 3, 1 Oct 80-30 Sep 81,
CAMBRIDGE UNIV (ENGLAND) DEPT OF METALLURGY AND MATERIALS SCIENCE
Pagination or Media Count:
Plasticity and fracture processes in engineering ceramics based on silicon carbide, silicon nitride, a sialon and boron carbide have been investigated as a function of temperature in the range 25 - 1000 C using indentation microhardness techniques. The effects of specimen microstructure on indentation processes were determined by using materials formed by a wide range of fabrication routes sintering, hot-pressing, reaction-bonding and pyrolytic deposition and comparison was made with the behaviour of single crystals SiC and Si. Microstructural characterization was carried out by light microscopy, electron-optical and X-ray techniques. The variation of Vickers and, in some cases, Knoop microhardness with temperature was measured, and deformation structures around indentations were examined optically and by scanning electron microscopy. Indentation plasticity in silicon carbide was further investigated by measuring Knoop hardness anisotropy on basal and non-basal faces of single crystal SiC at various temperatures. The effect of dopant on hardness was investigated for Si and SiC.
- Ceramics, Refractories and Glass