Fiber-reinforced composite material

Abstract

Briefly, a variety of embodiments of composite materials including part fabrication using composite materials is described.

1 .- 28 . (canceled) 
     
     
         29 . A method of forming a composite part comprising:
 heating a discontinuous fiber reinforced composite panel to a temperature so that the panel becomes pliable;   forming the heated panel in a manner so that it stretches to substantially conform to a mold having a shape that includes compound curves; and   cooling the shaped panel.   
     
     
         30 . The method of  claim 29 , wherein the forming includes: pressure forming the panel onto the mold via compression molding the heated panel with a compression tool that includes the mold in which the compression tool is closed so that the panel is pressed to a mold surface of the compression tool. 
     
     
         31 . The method of  claim 29 , wherein the forming the heated panel includes stretching the panel in a manner so that nearly all discontinuous fibers in the panel are in physical contact with or physically overlap with another discontinuous fiber before stretching and remain in physical contact with or continue to physically overlap with the another discontinuous fiber after stretching. 
     
     
         32 . The method of  claim 29 , wherein the dimensions of the part are in the range of from about 0.02 square meters to about 4 square meters. 
     
     
         33 .- 38 . (canceled) 
     
     
         39 . The method of  claim 31 , wherein the forming comprises vacuum forming in which a vacuum is initiated to remove air between the mold and the panel to permit the pliable panel to more tightly substantially conform to the shape provided by the mold. 
     
     
         40 . The method of  claim 29 , wherein the discontinuous fiber reinforced composite panel comprises at least two sheets with respective sheets comprising a composite of a matrix material and a reinforcement material. 
     
     
         41 . The method of  claim 40 , wherein the matrix material comprises one or more polymer materials and the reinforcement material comprises one or more fiber materials. 
     
     
         42 . The method of  claim 41 , wherein the one or more polymer materials comprises at least a thermoplastic and/or a thermoset polymer material. 
     
     
         43 . The method of  claim 42 , wherein the discontinuous fiber reinforced composite panel comprises a pair of mutually and immediately adjacent respective sheets in direct physical contact. 
     
     
         44 . The method of  claim 42 , wherein the discontinuous fibers in the respective sheets of the discontinuous fiber reinforced composite panel result from a respective pattern of slits in the respective sheets. 
     
     
         45 . The method of  claim 43 , wherein the pattern of slits in a respective sheet are offset aligned from the pattern of slits in an immediately adjacent sheet in a manner so that during the forming, that includes stretching the sheets, most, if not all, openings created at slit locations in the respective sheet are bridged during the forming by substantially parallel discontinuous reinforcing fibers of the immediately adjacent sheet. 
     
     
         46 . The method of  claim 42 , wherein the forming comprises a forming process in a manner so that nearly all discontinuous fibers in the panel in contact with or that physically overlap with another discontinuous fiber of an adjacent sheet remain in contact with or continue to physically overlap with the another discontinuous fiber of an adjacent sheet via limiting and/or controlling the stretching resulting from the forming process. 
     
     
         47 . The method of  claim 46 , wherein the forming comprises vacuum forming and wherein the vacuum forming uses conventional vacuum forming equipment. 
     
     
         48 . The method of  claim 47 , wherein the vacuum forming equipment includes the capability to heat different sections of the discontinuous fiber reinforced composite panel to different temperatures substantially in accordance with programming included as a component of the vacuum forming equipment. 
     
     
         49 . A method of cutting a pattern of slits in a uni-directional fiber reinforced polymer sheet comprising:
 placing the uni-directional fiber reinforced polymer sheet on a cutting bed using tension guides; and   cutting the pattern of slits in the uni-directional fiber reinforced polymer sheet while the uni-directional fiber reinforced polymer sheet is over the cutting bed between the tension guides.   
     
     
         50 . The method of  claim 49 , wherein the uni-directional fiber reinforced polymer sheet is fed over the cutting bed in a manner so that the uni-directional fiber reinforced polymer sheet unwinds from one spool prior to being cut with the pattern of slits and rewinds onto another spool after being cut with the pattern of slits. 
     
     
         51 . The method of  claim 50 , wherein the uni-directional fiber reinforced polymer sheet is fed through the tension guides via mechanical pulling. 
     
     
         52 . The method of  claim 49 , wherein the cutting the pattern of slits comprises cutting the pattern of slits with a laser or with a rotary blade. 
     
     
         53 . The method of  claim 52 , and further comprising: programming the laser or the rotary blade in advance to cut the pattern of slits.