[0002] The present invention relates to fiber reinforced resin matrix composites and, more particularly, to a composite laminated structure which resists splintering typical from ballistic impacts.
[0003] Articles fabricated from fiber reinforced resin matrix composite materials, e.g., Kevlar, graphite, and fiberglass, are known and have found increasing use in load bearing structural applications due to their high strength, light weight, and ability to be fashioned into complex shapes. Such composite structural materials are particularly suitable for aircraft structures.
[0004] A composite component is typically formed through a lay-up of composite material layers. The lay-up technique employs the use of a multiple of discrete plies of a substrate material having a plurality of parallel fibers that are impregnated with a resinous material. The multiple of layered plies are laminated in a mold and then placed in an autoclave or oven for application of heat and pressure such that the lay-up cures into the finished composite component.
[0005] To maximize the benefits of composites, it is essential that the fiber orientation be optimally tailored to meet the strength and stiffness requirements for a particular application. Disadvantageously, the outermost layers or plies of the composite component include a single fiber orientation, which may be subject to splintering or peeling in response to impact hazards. Since composites have relatively low interlaminar peel strength, the splinters may become relatively long. These elongated splinters may compromise structural integrity. A relatively small puncture may thus damage a relatively larger area. Even if integrity is not an issue, the repair covers a large area through which the splinter extends.
[0006] Accordingly, it is desirable to provide a composite laminate which resists splintering when damaged particularly from ballistic impact.
[0007] The composite component according to the present invention includes splinter arrestors laminated transverse to the fiber orientation of an outermost composite material layer.
[0008] The splinter arrestors are tows located upon the outermost composite material layers at a predetermined distance from each other. The predetermined distance is a distance which will constrain a splinter of fibers from the outermost composite material layers to an acceptable length. Alternatively or in addition, tows may be eliminated in subsurface layers to avoid an increase in the overall weight of the composite component.
[0009] The present invention therefore provides a composite laminate which resists splintering when damaged, particularly from ballistic impact.
[0010] The various features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the currently preferred embodiment. The drawings that accompany the detailed description can be briefly described as follows:
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[0016] Each material layer
[0017] To prevent peeling of the outermost composite material layers
[0018] The splinter arrestors
[0019] Referring to
[0020] The foregoing description is exemplary rather than defined by the limitations within. Many modifications and variations of the present invention are possible in light of the above teachings. The preferred embodiments of this invention have been disclosed, however, one of ordinary skill in the art would recognize that certain modifications would come within the scope of this invention. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. For that reason the following claims should be studied to determine the true scope and content of this invention.