GB8927734D0 - A composite material - Google Patents

Abstract

A composite material is manufactured from two spaced stacks (2 and 4) of intermediate fabric material. Each stack consists of a plurality of layers of material placed together face to face. Each layer is formed by embedding high strength fibres having a high modulus of elasticity in a resin matrix. The stacks (2 and 4) are removed from a release film (6), and a film of adhesive is applied to the lower surface of the side portion (8) of the stack (2) and the upper surface of the side portion (10) of the stack (4). These side portions (8 and 10) are placed in overlapping relationship, and are then crimp fastened together by a plurality of fasteners (12). Further layers (14 and 16) of intermediate fabric material are placed over the side portions (8 and 10) to cover the fasteners (12). The crimp fastened stacks (2 and 4) are placed in a mould tool comprising a base plate (18) and a top mould plate (20). A vacuum bag (22) is placed over the top mould plate (20), and an air tight seal is made between the vacuum bag (22) and the base plate (18) by means of a peripheral sealer tape (24). The space inside the vacuum bag (22) is evacuated by withdrawing air through a passage (34) at one edge of the vacuum bag (22). The fastened stacks (2 and 4) are compressed by bringing together the plates (18 and 20), and the mould tool and vacuum bag assembly is then heated in an autoclave to cure the stacks (2 and 4) while they remain under pressure to form the required composite material. After the curing operation has been completed, the mould tool and vacuum bag assembly is removed from the autoclave, the vacuum bag (22) is removed, the mould plates (18 and 20) are separated, and the cured composite material is removed.