| Popis: |
Hafnia-based composites containing either graphite or tungsten were investigated as rocket nozzle throat inserts in solid propellant rocket engines. The thermal shock resistance of these materials is considered in terms of macroscopic thermal conductivity, thermal expansion, modulus of elasticity (E), and compressive fracture stress (σE). The effect of (a) degree of hafnia stabilization, (b) density, and (c) graphite or tungsten content upon these parameters is discussed. The variation of the σE /E ratio with density and its effect upon thermal shock resistance of these materials is discussed in detail. |
