Composite Core and Method of Making Same

Abstract

A composite core includes a plurality of tubes, each the plurality of tubes comprising a plurality of fibers disposed in a polymeric matrix. Adjacent tubes of the plurality of tubes are adhesively bonded to one another along sides of the adjacent tubes. A method of making a composite core includes the steps of providing a plurality of tubes, each of the plurality of tubes including a plurality of fibers disposed in a polymeric matrix, and adhesively bonding adjacent tubes of the plurality of tubes along sides of the adjacent tubes. A method of making a composite core such that a removable band is included in the core, the removable band being configured to be removable through a procedure subsequent to the cure of the composite core, thereby producing gaps in the core.

What is claimed is: 
     
         1 . A method of making a composite core sandwich structure, comprising:
 providing a plurality of tubes, each of the plurality of tubes including a plurality of fibers disposed in a polymeric matrix;   using a mandrel to provide an internal form for the plurality of fibers of each of the plurality of tubes;   placing the plurality of fibers of each tube in contact with the plurality of fibers of adjacent tubes, such that the plurality of fibers of adjacent tubes have a crosslinked orientation;   bonding a first face sheet to a first end portion of the plurality of tubes; and   bonding a second face sheet to a second end portion of the plurality of tubes.   
     
     
         2 . The method, according to  claim 1 , wherein the mandrel is a round expandable mandrel such that the round expandable mandrel expands when heated while being confined in an arrangement so as to form each tube in a hexagonal shape. 
     
     
         3 . The method, according to  claim 1 , wherein the providing the plurality tubes is accomplished by:
 providing the plurality of fibers as a braided sleeve;   curing a polymeric resin about the plurality of fibers of the braided sleeve to form the polymeric matrix.   
     
     
         4 . The method, according to  claim 3 , further comprising:
 infusing the polymeric resin into the braided sleeve before the curing the polymeric resin.   
     
     
         5 . The method, according to  claim 1 , wherein the providing the plurality of tubes is accomplished at least in part by a filament winding process. 
     
     
         6 . The method, according to  claim 1 , wherein the providing the plurality of tubes is accomplished at least in part by a fiber placement process.