Manufacture of cmc articles having small complex features

Abstract

The present invention is ceramic matrix composite gas turbine engine component comprising a plurality of cured ceramic matrix composite plies, each ply comprising ceramic fiber tows, each ceramic fiber tow comprising a plurality of ceramic fibers, the tows in each ply lying adjacent to one another such that each ply has a unidirectional orientation. The component further comprises a layer of a coating on the ceramic fibers. The component further comprises a ceramic matrix material lying in interstitial regions between the fibers and tows of each ply and the interstitial region between the plurality of plies, wherein at least a portion of the component is no greater than about 0.021 inch thick. The present invention is also a method for making such a ceramic matrix composite component.

1 - 13 . (canceled) 
   
   
       14 . A method for manufacturing an uncooled ceramic matrix composite gas turbine engine component comprising the steps of:
 providing a plurality of prepreg ceramic plies, the plies comprising prepreg ceramic fiber tows, the tows in each ply lying adjacent to one another in a planar arrangement such that each ply has a unidirectional orientation;   laying up the plurality of prepreg ceramic plies in a preselected arrangement to form a component shape;   heating the component shape to form a ceramic preform; and   densifying the turbine blade preform with at least silicon to form an uncooled ceramic matrix composite turbine blade, wherein at least a portion of the component comprises cured ceramic plies having a thickness in the range of about 0.005 inch to about 0.007 inch, inclusive of tows, coating, and interstitial ceramic matrix material.   
   
   
       15 . The method of  claim 14 , wherein the step of laying up comprises laying up to form a component shape that comprises an airfoil. 
   
   
       16 . The method of  claim 14 , wherein the fiber tows are silicon carbide fiber tows. 
   
   
       17 . A method for manufacturing a cooled ceramic matrix composite gas turbine engine component comprising the steps of:
 providing a plurality of prepreg ceramic plies, the plies comprising prepreg ceramic fiber tows, the tows in each ply lying adjacent to one another in a planar arrangement such that each ply has a unidirectional orientation;   laying up the plurality of prepreg ceramic plies in a preselected arrangement around tooling to form a component shape;   heating the component shape to form a ceramic preform;   removing the tooling;   densifying the preform with at least silicon to form a ceramic matrix composite component wherein at least a portion of the component comprises cured ceramic plies having a thickness in the range of about 0.005 inch to about 0.007 inch, inclusive of tows, coating, and interstitial ceramic matrix material; and   drilling cooling holes in the ceramic matrix composite component to form a cooled ceramic matrix composite component.   
   
   
       18 . The method of  claim 17 , wherein the step of laying up comprises laying up to form a component shape that comprises an airfoil. 
   
   
       19 . The method of  claim 17 , wherein the step of laying up comprises laying up to form a component shape that is a turbine blade. 
   
   
       20 . The method of  claim 17 , wherein the ceramic fiber tows are silicon carbide fiber tows.