Composite material impregnated with metal silicide and process for producing the same

Abstract

There is provided a composite material that retains mechanical strength at a given level and at the same time, has a good balance in terms of lightweight properties and resistance to oxidation and a process for production thereof. Achievement is brought about by a composite material that can be produced by impregnating a particular metal silicide into a C/C composite or a carbonaceous composite material utilizing the C/C composite as starting material.

What is claimed is:  
     
         1 . A composite material impregnated with a metal silicide, which comprises a metal silicide and a C/C composite impregnated with at least the metal silicide.  
     
     
         2 . The composite material according to  claim 1 , wherein said metal silicide has a melting point of at least 1400° C. or higher.  
     
     
         3 . The composite material according to  claim 2 , wherein said metal silicide is at least one selected from the group consisting of titanium silicide, zirconium silicide, tantalum silicide, niobium silicide, chromium silicide, tungsten silicide, and molybdenum silicide.  
     
     
         4 . The composite material according to  claim 1 , wherein said C/C composite is tubular, cylindrical, perforated-disc-shaped, or angular.  
     
     
         5 . The composite material according to  claim 1 , wherein said C/C composite is composed of carbon and carbon fibers, and has a porosity of 5% to 50% before impregnation of the metal silicide.  
     
     
         6 . A process for producing a composite material comprising a metal silicide and a C/C composite impregnated with at least the metal silicide, wherein a basal material and a metal silicide is held in an inert atmosphere at a temperature in the vicinity of a melting point of the metal silicide for a desired period of time to impregnate a C/C composite as a basal material with the metal silicide, wherein the basal material is selected from the group consisting of C/C composites and carbonaceous composite materials in which a C/C composite is used as a starting material.  
     
     
         7 . The process for producing a composite material according to  claim 6 , wherein said metal silicide has a melting point of at least 1400° C. or higher.  
     
     
         8 . The process for producing a composite material according to  claim 6 , wherein said metal silicide is at least one selected from the group consisting of titanium silicide, zirconium silicide, tantalum silicide, niobium silicide, chromium silicide, tungsten silicide, and molybdenum silicide.  
     
     
         9 . The process for producing a composite material according to  claim 6 , wherein said metal silicide is impregnated at an amount in t he range of 1% to 50% by weight.