Multilayered boron nitride/silicon nitride fiber coatings

Abstract

A composite is described which has particular utility in the formation of components for gas turbine engines. The composite broadly comprises a substrate having a surface and at least one layer of a BN/Si 3 N 4 coating on the substrate surface. The coating preferably is formed by alternative layers of a BN material and a Si 3 N 4 material. The substrate may be a cloth material with fibers, such as SiC fibers, woven therein.

1 - 10 . (canceled) 
   
   
       11 . A system for forming a coating on a substrate, comprising:
 a reaction chamber for holding said substrate to be coated; and   means for forming a multilayered BN/Si 3 N 4  coating on said substrate.   
   
   
       12 . The system according to  claim 11 , wherein said coating forming means comprises a first tube for introducing nitrogen and ammonia into said reaction chamber and a second tube for introducing a halogen precursor into said reaction chamber while said nitrogen and ammonia are flowing into said reaction chamber. 
   
   
       13 . The system according to  claim 12 , wherein said second tube is within said first tube. 
   
   
       14 . The system according to  claim 11 , further comprising means for heating said substrate to a desired deposition temperature. 
   
   
       15 . The system according to  claim 14 , wherein said heating means comprises at least one induction heating coil. 
   
   
       16 - 19 . (canceled)