摘要:
A non-crimped, unidirectional fabric. The fabric includes a plurality of non-crimped, unidirectional fibers arranged parallel to one another. Weft fibers are arranged perpendicular to the non-crimped, unidirectional fibers. Warp fibers are arranged parallel to the non-crimped, unidirectional fibers. The weft fibers are woven around the non-crimped, unidirectional fibers and around the warp fibers without crimping the unidirectional fibers. A non-woven thermoplastic fabric is secured, such as by melt bonding, to the non-crimped unidirectional fibers to act as a toughening layer and improve the impact resistance of the fabric after it is molded into a part. The resulting fabric has excellent end-to-end uniformity, excellent resistance to fluids often encountered in aerospace and commercial aircraft applications, is readily adapted for use with conventional liquid-molding operations, and is ideally suited to aerospace and aircraft manufacturing applications where lightweight yet structurally strong component parts are needed.
摘要:
Materials and methods are provided for producing preform materials for impact-resistant composite materials suitable for liquid molding. Interlayers formed of nonwoven, continuous fibers, such as spunbonded, spunlaced, or mesh fabric, are introduced between non-crimped layers of unidirectional reinforcing fibers to produce a preform for use in liquid-molding processes to produce a composite member. Curing of the preform provides increased impact resistance by increasing the amount of energy required to propagate localized fractures due to impact.
摘要:
A dry fiber preform having a plurality of fiber layers held together via one or more non-woven, thermoplastic veils. The thermoplastic veils are heated and slightly melted during manufacture of the preform, and serve to hold the various woven fiber layers of the preform adjacent one another without stitching, clamping or tackifiers that could otherwise disrupt the flow of resin when the preform is subjected to a subsequently performed resin transfer molding process. The thermoplastic veils also serve to significantly improve the post-impact strength of the preform. The use of the thermoplastic veils allows the woven fiber layers to be secured to one another on the fly as the fiber layers are placed over a mold or tool and heated.