Gm. Song et al., Elevated temperature ablation resistance and thermophysical properties of tungsten matrix composites reinforced with ZrC particles, J MATER SCI, 36(19), 2001, pp. 4625-4631
In order to improve the elevated temperature ablation resistance of the cop
per infiltrated tungsten materials (Cu/W) which are used as the rudders of
the rocket motors at present, a new kind of tungsten matrix composites rein
forced by 30 vol% zirconium carbide particles (ZrCp/W) was developed, and t
he elevated temperature ablation resistance and thermophysical properties o
f the new materials were investigated. The values of the mass ablation rate
and linear ablation rate of ZrCp/W were much lower than that of Cu/W, whic
h indicated that the addition of ZrC particles in tungsten matrix remarkabl
y increased the ablation resistance. Thermal thermochemical oxidation of tu
ngsten and ZrC particles was the main ablation mechanism of ZrCp/W. A self-
made dynamic responding multi-wavelength pyrometer was employed to measure
the ablated surface temperatures and a thermal couple was employed to measu
re the back surface temperatures. The important temperature curves of the a
blated surface and back surface of the specimens were successfully detected
online, which indicated that ZrCp/W has good thermal shock resistance. The
present of ZrC particles in tungsten matrix remarkably decreased the therm
al conductivity and thermal diffusivity of the ZrCp/W composites, which is
very useful for increasing the elevated temperature ablation resistance of
the composites. The excellent elevated temperature ablation resistance of Z
rCp/W is attributed to the lower thermal conductivity, lower thermal diffus
ivity, oxidation resistance and high melting points. The good properties of
ZrCp/W makes it be suitable for the rudders for rocket motors instead of C
u/W. (C) 2001 Kluwer Academic Publishers.