Bae Systems Tensylon H.p.m., Inc.

Bae Systems Aerospace & Defense Group Inc.

Bae Systems Tensylon High Performance Materials, Inc.

Bae System Tensylon H.p.m., Inc.

E.i. Dupont De Nemours and Company

Dupont Safety & Construction, Inc.

Lisa Owen

Gene C Weedon

Kenneth C Harding

Jeffrey A Mears

Fielder Stanton Lyons

Joseph Mitchell

Peter Anthony Russell

Erik Johnson

Valent Horvatich

Michael McElroy

Brian H Jones

Joe Mitchell

Methods for manufacturing a protective helmet for the military and other uses are disclosed. Embodiments of the method include winding ballistic-tolerant tape or fibers to create a preform, placing the preform into a first mold member having an interior that defines a helmet-shaped cavity, and pressing together the first mold member against a second mold member that includes a pressurized bladder member. The method may further include pressurizing the bladder until the first and second mold members are heated and adhesives have melted or cured. The first and second mold members are cooled and the preform is removed from the first and second mold members.

Method of producing light weight protective helmets for military and other uses

A ballistic-resistant panel in which the entire panel or a strike-face portion thereof is formed of a plurality of sheets of high modulus high molecular weight polyethylene tape. The sheets of high modulus polyethylene tape can be in the form of cross-plied laminated layers of tape strips or a woven fabric of tape strips. The strips of UHMWPE tape include a width of at least one inch and a modulus of greater than 1400 grams per denier. The ballistic-resistant panel may include a backing layer of conventional high modulus fibers embedded in resin. A wide variety of adhesives were found acceptable for bonding the cross-plied layers of high modulus polyethylene tape together for forming the ballistic-resistant panels of the present invention.

Ballistic-resistant panel including high modulus ultra high molecular weight polyethylene tape

A process for the production of a non-fibrous ultra high molecular weight polyethylene tape having a width of 1-inch or greater and a modulus of 1,400 grams per denier or greater. The non-fibrous UHMWPE tape is obtained by compression molding ultrahigh molecular weight polyethylene powder at a temperature below its melting point and then drawing and stretching the entire resultant compression molded UHMWPE sheet, with no slitting or splitting of the sheet, at a draw ratio of at least 100:1. The UHMWPE tape can be produced in weights of 6,000 to 90,000 denier or greater. The UHMWPE tape of the present invention minimizes the effect of stress concentrators that are prevalent with fibers and thereby enables the tape to be drawn at much higher draw ratios than is possible with fibrous UHMWPE. When used in ballistics panels, the high modulus high molecular weight polyethylene tape of the present invention improves ballistic performance by providing enhanced dissipation of the impact energy of a projectile.

Non-fibrous high modulus ultra high molecular weight polyethylene tape for ballistic applications

A non-fibrous ultra high molecular weight polyethylene tape having a width of 1-inch or greater and a modulus of 1,400 grams per denier or greater. The non-fibrous UHMWPE tape is obtained by compression molding ultrahigh molecular weight polyethylene powder at a temperature below its melting point and then drawing and stretching the entire resultant compression molded UHMWPE sheet, with no slitting or splitting of the sheet, at a draw ratio of at least 100:1. The UHMWPE tape can be produced in weights of 6,000 to 90,000 denier or greater. The UHMWPE tape of the present invention minimizes the effect of stress concentrators that are prevalent with fibers and thereby enables the tape to be drawn at much higher draw ratios than is possible with fibrous UHMWPE. When used in ballistics panels, the high modulus high molecular weight polyethylene tape of the present invention improves ballistic performance by providing enhanced dissipation of the impact energy of a projectile.

A ballistic resistant panel including a strike face portion and a backing portion. The strike face portion includes a plurality of interleaved layers of non-fibrous ultra high molecular weight polyethylene tape. The backing portion includes a plurality of interleaved layers of cross-plied fibers of ultra high molecular weight polyethylene. The entire stack of interleaved layers is compressed at high temperature and pressure to form a ballistic resistant panel having a strike face on one side. It has been found that ballistic resistance increases as the weight ratio of the strike face portion with respect to the backing portion decreases. A composite panel having a strike face Tensylon tape with at most 40% of the total weight of the panel exhibits improved ballistic resistance properties as compared to a monolithic structure of strictly interleaved layers of cross-plied high modulus fibers.

A ballistic-resistant molded article having a sandwich-type structure including two outer portions of a first high modulus material surrounding an inner portion of a second high modulus material. The outer portions are comprised of a plurality of interleaved layers of adhesive coated cross-plied non-fibrous ultra high molecular weight polyethylene tape. The inner portion is comprised of a plurality of interleaved layers of high modulus cross-plied fibers embedded in resin. The stack of interleaved layers is compressed at high temperature and pressure to form a hybrid sandwich ballistic-resistant molded article that includes a mix of high modulus materials. It has been found that ballistic resistance is higher for the hybrid structure than for a monolithic structure of comparable areal density.

Ballistic-resistant article including one or more layers of cross-plied uhmwpe tape in combination with cross-plied fibers

A wide sheet of highly oriented ultra high molecular weight polyethylene comprising a plurality of strips of highly oriented ultra high molecular weight polyethylene partially overlapped or abutted longitudinally to define joints between adjoining strips wherein the thickness of the joint is less than about 80% of the thickness of the sum of the thicknesses of the adjoining strips that make up the joint. A continuous method for the production of such materials comprising subjecting longitudinally overlapping or abutted strips of these materials to temperatures below the melting point of the UHMWPE and pressures over 300 pli is also disclosed.

Wide ultra high molecular weight polyethylene sheet and method of manufacture

A non-woven ballistic material that demonstrates exceptional ballistic properties which ballistic material is fabricated by the lamination or angular lamination of a plurality of wide sheets of UHMWPE comprising a plurality of strips of highly oriented ultra high molecular weight polyethylene partially overlapped or abutted longitudinally to define joints between adjoining strips wherein the thickness of the joint is less than about 80% of the thickness of the sum of the thicknesses of the adjoining strips that make up the joint.

Growing community of inventors

Charlotte, NC, United States of America

Lisa Owen