Isostatic side-pressure shielded composite consolidation

Abstract

A mold for use in the production of a ballistic article from a composite laminate stacked material wherein the mold has a sliding sealing section that nests with a outer perimeter section and base portion so as to shield the sides of the composite laminate stacked material from applied isostatic pressure applied when in an autoclave. By shielding the sides of the composite laminate stacked material excess resin matrix material can be forced from the composite laminate stacked material to provide a uniform composite article with reduced weight and reduced thickness.

1 . An isostatic composite consolidation apparatus or mold, comprising a fixture that shields the sidewalls of a laminate from pressure whilst the laminate and fixture are together exposed to isostatic pressure. 
     
     
         2 . The isostatic composite consolidation apparatus or mold of  claim 1 , wherein the said fixture comprises a circumferential section that provides pressure shielding of the laminate sidewall, an enclosing profiled section that governs a curvature of the laminate and a sealing section. 
     
     
         3 . The isostatic composite consolidation apparatus or mold of any one of  claim 1  or  2 , wherein the said sealing section contains an opening that allows direct application of isostatic pressure to all but the perimeter of the laminate surface it contacts. 
     
     
         4 . The isostatic composite consolidation apparatus or mold of any one of  claims 1 - 3 , wherein the said enclosing profile section and the said sealing section both contact the said circumferential section and the non-sidewall laminate faces and form a sealed void between the said circumferential section and the sidewalls of the laminate. The said sealing section and the said enclosing profiled section are able to move towards each other under pressure and, in preference, their opposing faces are an offset of the same profile, dictated by the laminate thickness. 
     
     
         5 . The isostatic composite consolidation apparatus or mold of any one of the above claims, wherein the laminate and said fixture are enclosed in a silicone membrane and heat-sealed in a disposable plastic bag, fused with the contents and surrounds under vacuum. 
     
     
         6 . The isostatic composite consolidation apparatus or mold of any one of the above claims, wherein the said silicone membrane is comprised of multiple separate sections. 
     
     
         7 . The isostatic composite consolidation apparatus or mold of any one of the above claims, wherein the said silicone membrane is adequately soft as to transfer the applied pressure to the exposed laminate and said fixture surfaces without significant loss of isostatic nature. 
     
     
         8 . A process of isostatic composite consolidation using the apparatus or mold of any one of the above claims, wherein the said heat-sealed disposable plastic bag containing the said silicone membrane, said fixture and laminate are cycled through the simultaneous and controlled application of elevated isostatic pressure and temperature to consolidate the laminate. 
     
     
         9 . The isostatic composite consolidation apparatus or mold of any one of the above claims, wherein the said circumferential section, said enclosing profiled section and said sealing section are constructed from rigid and strong materials, such as metals, metal alloys or composites. 
     
     
         10 . The isostatic composite consolidation apparatus or mold of any one of the above claims, wherein the materials are thermally conductive. 
     
     
         11 . The isostatic composite consolidation process, apparatus or mold of any one of the above claims, wherein the application of pressure to the fixture acts to close interfaces between the said circumferential section and the said sealing section and enclosing profiled section. 
     
     
         12 . The isostatic composite consolidation apparatus or mold of any one of the above claims, wherein the said sealing section is engineered to elastically deform under pressure to maintain contact with the said circumferential section. 
     
     
         13 . The isostatic composite consolidation apparatus or mold of any of the above claims, wherein the circumferential section is non-circular. 
     
     
         14 . A mold for a ballistic article formed by consolidating a laminate stack, the mold including;
 a sliding sealing section, and   a base profile section having a circumferential upwardly extending side wall with an inner face and a base profile surface;   the circumferential upwardly extending side wall having an internal dimension that is greater than an outer dimension of the laminate stack to be consolidated;   wherein the sliding sealing section forms a sliding fit with the inner face of the circumferential upwardly extending side wall.   
     
     
         15 . The isostatic composite consolidation apparatus or mold of any one of the above claims, wherein the sealing section shields a lateral side of the laminate stack from external pressure. 
     
     
         16 . The isostatic composite consolidation apparatus or mold of  claim 14 , wherein the sliding sealing section has a “L”-shaped profile. 
     
     
         17 . The isostatic composite consolidation apparatus or mold of  claim 16 , wherein the base profile section slidingly nests within the sealing section. 
     
     
         18 . The isostatic composite consolidation apparatus or mold of  claim 17 , wherein the mold further includes a sealing ring. 
     
     
         19 . The isostatic composite consolidation apparatus or mold of  claim 17 , wherein the sealing ring is deformable. 
     
     
         20 . The isostatic composite consolidation apparatus or mold of  claim 17 , wherein the sealing ring is positioned on a rare face of the base profile. 
     
     
         21 . The isostatic composite consolidation apparatus or mold of any one of the above claims, wherein the internal dimension of the circumferential upwardly extending sidewall of the base profile section is between 0.001 mm to 25 mm greater than the outer dimension of the laminate stack to be consolidated. 
     
     
         22 . The isostatic composite consolidation apparatus or mold of any one of the above claims, wherein the sealing section is a ring or band. 
     
     
         23 . The isostatic composite consolidation apparatus or mold of any one of the above claims, wherein the sliding sealing section is a ring or a band having an angled profile. 
     
     
         24 . The isostatic composite consolidation apparatus or mold of any one of the above claims, wherein the sliding sealing section is a ring or a band having a bevelled profile. 
     
     
         25 . The isostatic composite consolidation apparatus or mold of any one of the above claims, wherein the sliding sealing section is a ring or a band having an “L”-shaped profile. 
     
     
         26 . The isostatic composite consolidation apparatus or mold of any one of the above claims, wherein the sealing section is a hoop or band having a substantially constant profile. 
     
     
         27 . The isostatic composite consolidation apparatus or mold of any one of the above claims, wherein the sealing section is deformable. 
     
     
         28 . The isostatic composite consolidation apparatus or mold of any one of the above claims, wherein the base profile section is two-piece. 
     
     
         29 . The isostatic composite consolidation apparatus or mold of any one of the above claims, wherein the base profile section is two-piece, including a base profile section and a circumferential section. 
     
     
         30 . The isostatic composite consolidation apparatus or mold of  claim 23 , wherein a sealing membrane is located between the sealing section and the laminate stack to be consolidated. 
     
     
         31 . The isostatic composite consolidation apparatus or mold of any one of the above claims, wherein the mold is a molding tool. 
     
     
         32 . A process for the preparation of a molded article including the steps of:
 forming a stack of laminate material;   providing an isostatic pressurizing means;   placing the stack of laminate material in a mold, the mold having a sliding sealing section, and   a base profile section having a circumferential upwardly extending side wall with an inner face and a base profile surface;   the circumferential upwardly extending side wall of the base profile section having an internal dimension that is greater than an outer dimension of the laminate stack to be consolidated;   applying an isostatic pressure to the external surfaces of the sliding sealing ring;   wherein the sliding sealing section forms a sliding fit with the inner face of the circumferential upwardly extending side wall under the isostatic pressure.   
     
     
         33 . The isostatic composite consolidation process, apparatus or mold of any one of the above claims, wherein the molded article is a ballistic article. 
     
     
         34 . The isostatic composite consolidation process, apparatus or mold of any one of the above claims, wherein the sealing section is deformable. 
     
     
         35 . The isostatic composite consolidation process, apparatus or mold of any one of the above claims, wherein the stack of laminate material has a top surface, bottom surface and a side surface. 
     
     
         36 . The isostatic composite consolidation process, apparatus or mold of any one of the above claims, wherein the isostatic pressure is prevented from being applied the side surface of the laminate material.