Method for preparing pre-form materials

摘要

A pre-form and a method of preparing pre-forms are provided. The pre-forms comprise a resin and at least three layers of oriented fiber tows. The pre-forms comprise fiber tows instead of the traditional prepregs to enhance rearranging of resin and/or fibers during subsequent processing as well as provide greater freedom, a price reduction and/or a reduction of waste. The pre-forms may be formed three-dimensionally to enhance coupling to further pre-forms or other structures and/or to enhance shaping of the pre-form to a final three-dimensional shape. The method of preparation of pre-forms involves providing an adhesive between layers of fibers and providing a resin in contact with at least one of the layers of fibers. The resin is preferably provided in a non-continuous layer to allow for removal of gas at least partially in a direction orthogonal to the layers of resin. Advantageously, during manufacturing, the fibers are placed with an exact start and ending location, thereby avoiding waste. The pre-forms are suitable for preparation of composite structures like for example spars for wind turbine blades.

主权项

1. A pre-form, comprising:
a resin, an adhesive, and at least four layers of oriented fibre tows, said at least four layers of fibre tows in the pre-form comprising first type fibres and second type fibres provided in separate layers, such that second type fibre layers containing said second type fibres are interleaved between first type fibre layers containing said first type fibres so as to define an interleaved region proximate one longitudinal end of the pre-form, said second type fibre layers are separated from one another by said first type fibre layers in the interleaved region, wherein said first type fibre layers include first terminal ends located in the interleaved region and second terminal ends at an opposite longitudinal end of the pre-form from the interleaved region, said adhesive is located between adjacent layers of oriented fibre tows to at least partially immobilize said fibres, a part of the pre-form is formed three-dimensionally so that said part of the pre-form is tapered along a tapered connection surface defined in the interleaved region by the first terminal ends of said first type fibre layers, wherein said second type fibre layers include first terminal ends located on one side of said tapered connection surface and outside the interleaved region, and said second type fibre layers include second terminal ends located in the interleaved region and on an opposite side of said tapered connection surface from the first terminal ends of the second type fibre layers, and wherein said second type fibres do not contain the same fibre material as said first type fibres, and the pre-form is enhanced for coupling of the pre-form at said tapered connection surface to a separate composite member comprising said second type fibres and a resin by having the second type fibre layers extend from the interleaved region through and beyond the tapered connection surface such that the first terminal ends of said second type fibre layers are positioned to extend toward the separate composite member comprising said second type fibres when the separate composite member is coupled to the pre-form at the tapered connection surface.