Abstract: Construction and advantages of improved wavy composite structures made from wavy composite, unidirectional composites, and damping materials is revealed. By combining wavy composite laminae in various waveforms, offsets, angular orientations and material combinations, it is possible to provide axial, torsion, or shear properties equivalent to unidirectional materials but without the limitations related to fiber discontinuity, labor costs for fabrication, and weakness at seams where laminates overlap. By combining wavy composite layers with unidirectional crossplies, or by using woven mats with various fill fiber levels where the warp fibers are sinuously arranged, improved strength and damping is possible. Several examples of both wavy crossply laminates and unidirectional crossply laminates are analyzed and compared.

Abstract: An improved method for the manufacturing of wavy pre-preg material that moves a first group of rollers in a transverse and a longitudinal direction with respect to a second group of rollers, to place a sinuous waveform in a fiber reinforced matrix for the manufacture of a wavy pre-preg material. The fabrication of wavy fiber pre-preg (fibers pre-impregnated with epoxy resin as an example) can be accomplished with an automated control system that permits the creation of non-periodic or mixed waveforms. The improved apparatus for this process allows for a more accurate placement of fibers, production of a wider variety of usable waveforms, and increased quality of pre-preg produced.

Abstract: Construction and advantages of improved wavy composite structures made from wavy composite, unidirectional composites, and damping materials is revealed. By combining wavy composite laminae in various waveforms, offsets, angular orientations and material combinations, it is possible to provide axial, torsion, or shear properties equivalent to unidirectional materials but without the limitations related to fiber discontinuity, labor costs for fabrication, and weakness at seams where laminates overlap. By combining wavy composite layers with unidirectional crossplies, or by using woven mats with various fill fiber levels where the warp fibers are sinuously arranged, improved strength and damping is possible. Several examples of both wavy crossply laminates and unidirectional crossply laminates are analyzed and compared.

Abstract: An improved method for the manufacturing of wavy pre-preg material that moves a first group of rollers in a transverse and a longitudinal direction with respect to a second group of rollers, to place a sinuous waveform in a fiber reinforced matrix for the manufacture of a wavy pre-preg material. The fabrication of wavy fiber pre-preg (fibers pre-impregnated with epoxy resin as an example) can be accomplished with an automated control system that permits the creation of non-periodic or mixed waveforms. The improved apparatus for this process allows for a more accurate placement of fibers, production of a wider variety of usable waveforms, and increased quality of pre-preg produced.

Abstract: An improved apparatus for the manufacturing of wavy pre-preg material that moves a first group of rollers in a transverse and a longitudinal direction with respect to a second group of rollers, to place a sinuous waveform in a fiber reinforced matrix for the manufacture of a wavy pre-preg material. The fabrication of wavy fiber pre-preg (fibers pre-impregnated with epoxy resin as an example) can be accomplished with an automated control system that permits the creation of non-periodic or mixed waveforms. The improved apparatus for this process allows for a more accurate placement of fibers, production of a wider variety of usable waveforms, and increased quality of pre-preg produced.

Abstract: Construction and advantages of tubular structures made from wavy composite, conventional composites, and damping materials is revealed. The use of sinuous or wavy composite structures as a capable replacement for crossply laminates is disclosed. By combining wavy composite laminae in various waveforms, offsets, angular orientations and material combinations, it is possible to provide axial, torsion, or shear properties equivalent to unidirectional materials but without the limitations related to fiber discontinuity, labor costs for fabrication, and weakness at seams where laminates overlap. Several examples of both wavy crossply laminates and unidirectional crossply laminates are analyzed and compared.

Abstract: Fiber-reinforced composite structures and applications that exhibit inherent damping with little or no sacrifice in strength and that make use of wavy fiber patterns in the plane of the composite laminate. The invention includes the methods and apparatus for manufacturing the wavy composite material, and the use of the material in the construction of practical structures and devices. The fabrication of a wavy fiber pre-preg (fibers preimpregnated with epoxy resin as an example) can be accomplished with an automated control system that permits the creation of non-periodic or mixed wave forms. Combined with conventional laminate structures and/or materials, these wavy composite materials allow the design engineer to “tune” the dynamics (e.g. damping, stiffness) of a structural member. The use of wavy patterns in the laminate is not limited to the use of traditional epoxies but may also be used in conjunction with specialized matrix materials having inherent viscoelastic properties.