摘要 |
The invention provides a woven composite lightweight turbine blade in which, e.g. ceramic or carbon fibers are woven around a foam core in the airfoil section of the blade and around a removable mandrel in the dovetail section of the blade, and braided at the tip and root thereof to define a woven blade pre-form. An infiltrant of e.g. phenolic, carbon or ceramic is added to the woven pre-form, which is then pyrolized to provide a thermally stable matrix in the pre-form and define a composite woven blade therewith. The resulting blade has a cavity in the air foil section between the tip and root sections of the blade and a hollow dovetail section. The dovetail section has reinforcing carbon or ceramic fibers mounted across the resulting passageway through the dovetail, which fibers are cooled by air passing through such dovetail passage such that the dovetail acts as a heat exchanger for the so-formed woven composite blade. The so cavitied woven composite blade has the dual advantage of a) being lightweight and b) having the heat exchange passage noted above.
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