Composite Structures Having Reinforced Edge Bonded Joints and Method for Making the Same

Abstract

A ceramic matrix composite structure has a reinforced core for carrying loads. The core includes a web connected between the facesheets by edge bonded joints for transmitting compressive, tensile and shear loads. The edge bonded joints are laterally reinforced by bridging members bonded to the facesheets, on opposite sides of the webs. The bridging members may comprise low density, high temperature rigid foam.

1 . A ceramic matrix composite structure, comprising:
 at least one ceramic matrix composite sheet;   a stiffener extending transverse to the sheet and having at least one edge;   an edge bonded joint between the at least one edge of the stiffener and the sheet; and   bridging members on opposite sides of the stiffener for reinforcing the edge bonded joint.   
     
     
         2 . The ceramic matrix composite structure of  claim 1 , wherein:
 the edge bonded joint includes first and second bondlines between the stiffener and the sheet, and   the bridging members respectively cover the first and second bondlines.   
     
     
         3 . The ceramic matrix composite structure of  claim 2 , wherein each of the bridging members is bonded to the sheet 
     
     
         4 . The ceramic matrix composite structure of  claim 1 , wherein the sheet is a ceramic matrix composite. 
     
     
         5 . The ceramic matrix composite structure of  claim 1 , wherein the bridging members are each formed of a rigid foam having a density less than the density of the stiffener. 
     
     
         6 . The ceramic matrix composite structure of  claim 1 , further comprising a layer of rigid foam between the sheet and the bridging members. 
     
     
         7 . The ceramic matrix composite structure of  claim 1 , wherein the bridging members include a rigid ceramic foam. 
     
     
         8 . The ceramic matrix composite structure of  claim 1 , wherein the bridging members include a sintered ceramic fiber felt. 
     
     
         9 . The ceramic matrix composite structure of  claim 1 , further comprising foam insulation surrounding the stiffener. 
     
     
         10 . The ceramic matrix composite structure of  claim 9 , wherein the stiffener is a ceramic matrix composite. 
     
     
         11 . A ceramic matrix composite structure, comprising:
 first and second spaced apart ceramic matrix composite sheets;   a core sandwiched between the first and second composite sheets, the core including a web extending transverse to the first and second sheets and having opposite ends respectively bonded to the first and second composite sheets; and   first and second reinforcement layers abutting opposite sides of the web for reinforcing the bonds between the opposite ends of the web and the first and second composite sheets.   
     
     
         12 . The ceramic matrix composite structure of  claim 11 , wherein each of the first and second composite sheets include multiple plies of fiber fabric held in a ceramic matrix. 
     
     
         13 . The ceramic matrix composite structure of  claim 11 , wherein the web includes a fiber reinforced ceramic matrix. 
     
     
         14 . The ceramic matrix composite structure of  claim 11 , wherein each of the first and second reinforcement layers includes a rigid ceramic foam having a density less than the density of the web. 
     
     
         15 . The ceramic matrix composite structure of  claim 11 , wherein each of the first and second reinforcement layers includes a porous ceramic insulating material. 
     
     
         16 . The ceramic matrix composite structure of  claim 11 , wherein the core further includes foam insulation filling the space between the first and second composite sheets. 
     
     
         17 . The ceramic matrix composite structure of  claim 11 , wherein the stiffener is a ceramic matrix composite. 
     
     
         18 . The ceramic matrix composite structure of  claim 11 , wherein the first and second layers are respectively bonded to the first and second composite sheets. 
     
     
         19 . The ceramic matrix composite structure of  claim 11 , wherein each of the first and second reinforcement layers includes a bridging member having a bottom bonded to a corresponding one of the first and second facesheets and a side abutting one of the opposite sides of the web.