Pre-form and method of preparing a pre-form

摘要

A pre-form and a method of preparing pre-forms are provided. The pre-forms comprise a resin and at least two 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. 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 three layers of fibres, wherein:
a plurality of said layers of fibres consist exclusively of unidirectionally oriented, continuous fibre tows, the resin is consisting essentially of a thermosetting material and contains no thermoplastic materials, the adhesive is applied in a non-continuous layer between adjacent layers of fibres to at least partially immobilize the fibres and to define a plurality of gas escape pathways having pathway outlets directed in at least two orthogonal directions, the at least two orthogonal directions being transverse to the longitudinal orientation of the fibre tows such that the at least two orthogonal directions include a primary orthogonal direction oriented through a thickness defined by the plurality of said layers of fibres in combination and a secondary orthogonal direction oriented parallel to the plurality of said layers of fibres, and such that the gas escape pathways promote gas escape during curing or pre-curing of the resin and adhesive in the at least two orthogonal directions through the pathway outlets, and a part of said pre-form being formed three-dimensionally so that said part of said pre-form is tapered.