초록 ▼

The present invention generally relates to mechanisms for preventing undesirable oxidation (i.e., oxidation protection mechanisms) in composite bodies. The oxidation protection mechanisms include getterer materials which are added to the composite body which gather or scavenge undesirable oxidants w

The present invention generally relates to mechanisms for preventing undesirable oxidation (i.e., oxidation protection mechanisms) in composite bodies. The oxidation protection mechanisms include getterer materials which are added to the composite body which gather or scavenge undesirable oxidants which may enter the composite body. The getterer materials may be placed into at least a portion of the composite body such that any undesirable oxidant approaching, for example, a fiber reinforcement, would be scavenged by (e.g., reacted with) the getterer. The getterer materials) may form at least one compound which acts as a passivation layer, and/or is able to move by bulk transport (e.g., by viscous flow as a glassy material) to a crack, and sealing the crack, thereby further enhancing the oxidation protection of the composite body. One or more ceramic filler materials which serve as reinforcements may have a plurality of super-imposed coatings thereon, at least one of which coatings may function as or contain an oxidation protection mechanism. Specifically, a coating comprising boron nitride which has been engineered or modified to contain some silicon exhibits improved corrosion resistance, specifically to oxygen and moisture. The coated materials may be useful as reinforcing materials in high performance composites to provide improved mechanical properties such as fracture toughness. The present invention also relates to improved composites which incorporate these materials, and to their methods of manufacture.

대표청구항 ▼

[ What is claimed is:] [1.]1. A composite material, comprising:(a) a permeable mass or preform comprising a plurality of bodies of at least one filler material;(b) a matrix embedding said permeable mass or preform; and(c) at least one coating disposed between said bodies of at least one filler mater

[ What is claimed is:] [1.]1. A composite material, comprising:(a) a permeable mass or preform comprising a plurality of bodies of at least one filler material;(b) a matrix embedding said permeable mass or preform; and(c) at least one coating disposed between said bodies of at least one filler material and said matrix, said at least one coating comprising boron nitride having at least some silicon present in solution in said boron nitride; and(d) at least two zonal junctions, at least one of said zonal junctions being weak relative to the remaining zonal junction(s) to permit debonding and pull-out of said at least one filler material with respect to said matrix upon application of stress sufficient to cause fracture of said composite material.