PHOSPHATE-GLASS CERAMIC COBALT CHROMIUM COMPOSITE-MATERIALS

Phosphate glass-ceramic-cobalt-chromium particulate composites have been prepared by hot-pressing and their thermal, elastic and mechanical properties have been measured. Results have then been explained using various theoretical models on thermal properties, elasticity and fracture mechanics of particulate composites. It is shown that the evolution of average thermal expansion coefficients as a function of cobalt-chromium volume fraction agrees well with Turner's model [25]. In the same way, Young's moduli lie within Hashin and Shtrickman's upper and lower bounds [33], which means both a close contact between matrix and particles and no microcracking of materials. Strength and fracture toughness do not show significant evolutions with metal volume fraction. Fracture energy continuously decreases which produces both a nearly planar surface fracture and a poor bonding between matrix and particles.