Abstract:
Viscoelastic, lightweight composite armor that is resistant to backface deformation, and to a method for evaluating the effectiveness of composite armor in resisting backface deformation. The index of retraction of a composite is determined by evaluating the degree of composite retraction at the site of impact of projectile after movement of the projectile is stopped. The degree of retraction indicates the ability of the composite to resist backface deformation.
Abstract:
Highly uniform woven fibrous structures formed from fibrous tapes, wherein the tapes constitute the warp and weft tapes of a woven fabric. The individual fibrous tapes may be woven or non-woven, and may be formed as narrow tapes or may be cut from a wider fabric web.
Abstract:
A method for improving the translation efficiency of fiber strength into composite strength is provided. A single unidirectional tape, single unidirectional fiber web or a stack of unidirectional web/unidirectional tape plies formed from partially oriented fibers/tapes is primed under mild conditions followed by subjecting the primed plies to an axial extension stress in the axial fiber direction of each fiber ply by passage through a compression apparatus. The axial extension stress extends the fibers, strengthening them, while also compacting the plies together and thereby forming a composite having improved strength. Production yield is improved by avoiding maximal fiber stretching and thereby avoiding typical manufacturing loss, and low weight composite armor having increased strength is achieved.