Carbon-carbon friction material with improved wear life

Abstract

Carbon-carbon composite material article and method of manufacturing it. The carbon-carbon composite material comprises a carbonized woven or nonwoven fabric-based preform which is subjected to rapid densification, e.g. using a resin transfer molding process, and which may subsequently be infiltrated with a ceramic additive solution in order to improve wear and friction properties. The method comprises densifying the preform and subsequently adding a ceramic additive to it to infiltrate the material with the additive and enhance the properties of the final product.

1 . A method for manufacturing a carbon-carbon composite material article, said method comprising sequentially:
 providing a nonwoven material;   carbonizing the nonwoven material;   subjecting the nonwoven material to a first chemical vapor deposition/infiltration (CVD) and/or liquid resin/pitch densification procedure;   carbonizing the nonwoven material;   infiltrating the nonwoven material with a ceramic additive in suspension;   drying the nonwoven material; and   subjecting the nonwoven material to a second CVD or liquid resin/pitch densification procedure and to a heat treatment, before or after said second densification procedure, to set the ceramic additive.   
   
   
       2 . The method for manufacturing a carbon-carbon composite material article of  claim 1 , wherein the nonwoven material comprises a nonwoven preform. 
   
   
       3 . The method for manufacturing a carbon-carbon composite material article of  claim 2 , wherein the step of adding the ceramic additive occurs subsequent to densification of the nonwoven material to a density of at least 1.5 gm/cc. 
   
   
       4 . The method for manufacturing a carbon-carbon composite material article of  claim 3 , wherein densification of the material comprises subjecting the material to a resin transfer molding (RTM) process. 
   
   
       5 . The method for manufacturing a carbon-carbon composite material article of  claim 4 , wherein the resin transfer molding process utilizes pitch. 
   
   
       6 . The method for manufacturing a carbon-carbon composite material article of  claim 5 , wherein the pitch is a high viscosity pitch resin. 
   
   
       7 . The method for manufacturing a carbon-carbon composite material article of  claim 6 , wherein densification of the material further comprises a step of stabilizing the pitch. 
   
   
       8 . The method for manufacturing a carbon-carbon composite material article of  claim 7 , further comprising carbonizing or charring the pitch after the step of stabilizing. 
   
   
       9 . The method for manufacturing a carbon-carbon composite material article of  claim 1 , wherein the step of adding a ceramic additive comprises infiltrating the nonwoven material with a ceramic additive solution. 
   
   
       10 . The method for manufacturing a carbon-carbon composite material article of  claim 9 , wherein the step of infiltrating the nonwoven material with a ceramic additive comprises infiltrating the material with silica suspended in water. 
   
   
       11 . The method of  claim 1 , which comprises subjecting a carbonized nonwoven preform sequentially to CVD processing, then to rapid densification using a resin transfer molding (RTM) process with a high viscosity pitch resin, then to infiltration with silica suspended in water, then to CVD processing. 
   
   
       12 . A method for manufacturing a carbon-carbon composite material article comprising the sequential steps of:
 providing a nonwoven preform;   carbonizing the preform;   subjecting the preform to a first chemical vapor deposition procedure;   subjecting the preform to a resin transfer molding process with a high viscosity resin/pitch;   stabilizing the resin/pitch;   carbonizing or charring the resin/pitch;   infiltrating the preform with a solution of silica suspended in water;   drying the preform;   subjecting the preform to a second chemical vapor deposition procedure; and   heat treating the preform.   
   
   
       13 . A carbon-carbon composite material article manufactured by the process of  claim 1 . 
   
   
       14 . A carbon-carbon composite preform manufactured by the process of  claim 12 . 
   
   
       15 . The carbon-carbon composite material article of  claim 14 , wherein all silicon carbide particles in the article have an average diameter of less than 1 micron. 
   
   
       16 . The carbon-carbon composite material article of  claim 15 , wherein the weight percentage of silicon carbide in the article is less than 2%. 
   
   
       17 . A carbon-carbon composite material article comprising a carbonized nonwoven preform, wherein the preform is subjected to rapid densification using a resin transfer molding process and is subsequently infiltrated with silica suspended in water. 
   
   
       18 . The carbon-carbon composite material article of  claim 17 , wherein the preform is subjected to rapid densification using a resin transfer molding process with a high viscosity pitch resin. 
   
   
       19 . The carbon-carbon composite material article of  claim 18 , wherein the preform is subjected to a first chemical vapor deposition procedure prior to the step of densification. 
   
   
       20 . The carbon-carbon composite material article of  claim 19 , wherein the preform is subjected to a second chemical vapor deposition procedure subsequent to infiltration with silica suspended in water.