Composite components with integral protective casings

Abstract

Methods and compositions for fabricating composite parts including at least one structural material and at least one protective material that are integrally bonded without the use of secondary bonding operations. One or more of the materials forming the layers of the composite parts may be a ceramic composition with or without porosity and one or more of the materials may be a polymer composition. Methods including co-injection processes also are provided for fabricating multi-layered structures in which each layer serves a desired function while still being integrated into the overall structure.

1 . A method of fabricating a composite structure comprising:
 providing a mold having first and second slurry injection portions adjacent one another;   injecting a first slurry in the first portion and injecting a second slurry in the second portion while generally maintaining separation of the first and second slurries in the mold to form first and second layers respectively; and   curing the slurries to provide a composite structure having bonded first and second layers,   wherein at least one of first and second layers is effective for providing structural support and at least one of the first and second layers is effective for providing heat protection.   
   
   
       2 . The method of  claim 1  wherein at least one of the first and second layers is formed with a thickness effective for limiting heat transfer through the thickness of the layer. 
   
   
       3 . The method of  claim 2  wherein the layer has a porosity effective for reducing thermal conductivity of the layer for limiting transfer of heat through the layer. 
   
   
       4 . The method of  claim 1  wherein the slurries are injected simultaneously into the mold. 
   
   
       5 . The method of  claim 1  wherein the slurries are injected sequentially into the mold. 
   
   
       6 . The method of  claim 1  wherein the mold includes a third slurry injection portion adjacent the second portion and opposed from the first portion, the method including injecting a third slurry into the third portion. 
   
   
       7 . A method of forming a co-cured non-metallic composite part comprising:
 providing a mold having first and second slurry injection portions adjacent one another;   injecting a first slurry in the first portion;   injecting a second slurry in the second portion while generally maintaining separation of the first and second slurries in the mold to form first and second layers respectively, the second slurry including a ceramic composition; and   curing the slurries to provide a composite part having bonded first and second layers, the second layer having a porosity of at least about 20 percent by volume, and at least one of the first and second layers is effective for providing structural support and at least one of the first and second layers is effective for providing heat protection.   
   
   
       8 . The method of  claim 7  wherein at least one of the first and second layers is formed with a thickness effective for limiting heat transfer through the thickness of the layer. 
   
   
       9 . The method of  claim 8  wherein the layer has a porosity effective for reducing thermal conductivity of the layer for limiting transfer of heat through the layer. 
   
   
       10 . The method of  claim 7  wherein the slurries are injected simultaneously into the mold. 
   
   
       11 . The method of  claim 7  wherein the slurries are injected sequentially into the mold. 
   
   
       12 . The method of  claim 7  wherein the mold includes a third slurry injection portion adjacent the second portion and opposed from the first portion, the method including injecting a third slurry into the third portion. 
   
   
       13 . The method of  claim 7  wherein the first slurry is a polymer composite composition. 
   
   
       14 . The method of  claim 13  wherein the polymer composite composition is selected from the group consisting of fiberglass, vinyl ester, epoxy and mixtures thereof. 
   
   
       15 . The method of  claim 7  wherein both the first and the second slurries are a ceramic composition.