Energy absorbing articles

The article of clam 18, wherein said energy absorber comprises at least one material selected from the group consisting of plastic materials, metallic materials and composite materials.

An energy absorbing plastic article comprising:

• a plurality of auxetic structures, said auxetic structures having a size greater than about 1 mm;
• and
• at least one cell boundary structurally coupled to the auxetic structures, said at least one cell boundary configured to resist of a deformation of said auxetic structures, said at least one cell boundary at least partially surrounding the plurality of auxetic structures collectively and including a plurality of connectors extending into the auxetic structures to structurally couple the at least one cell boundary to the auxetic structures.

A method of manufacturing an energy absorbing plastic article, wherein the article comprises a plurality of auxetic structures, said auxetic structures having a size greater than about 1 mm, and at least one cell boundary structurally coupled to the auxetic structures, said at least one cell boundary configured to resist a deformation of said auxetic structures, said at least one cell boundary at least partially surrounding the plurality of auxetic structures collectively and including a plurality of connectors extending into the auxetic structures to structurally couple the at least one cell boundary to the auxetic structures, the method comprising:

• injection molding a plastic material to form the article, by injecting the plastic material into a mold, the mold comprising cavities corresponding to the auxetic structures and the cell boundary.

A method of manufacturing an energy absorbing plastic article, wherein the article comprises a plurality of auxetic structures having dimensions of length, width and depth, at least one of said dimensions being greater than 1 mm, and at least one cell boundary structurally coupled to the auxetic structures, said at least one cell boundary configured to resist a deformation of said auxetic structures, said at least one cell boundary at least partially surrounding the plurality of auxetic structures collectively and including a plurality of connectors extending into the auxetic structures to structurally couple the at least one cell boundary to the auxetic structures, the method comprising:

• extruding a plastic material to form the article, wherein said extrusion comprises forcing the plastic material through a die, the die comprising a cross section complimentary to the auxetic structures and the cell boundary.

An automotive energy absorber comprising a plurality of auxetic structures, and at least one cell boundary structurally coupled to the auxetic structures, said auxetic structures having a size greater than about 1 mm, said at least one cell boundary configured to resist a deformation of said auxetic structures, said at least one cell boundary at least partially surrounding the plurality of auxetic structures collectively and including a plurality of connectors extending into the auxetic structures to structurally couple the at least one cell boundary to the auxetic structures.

An automotive bumper comprising an energy absorber, said energy absorber comprising a plurality of auxetic structures and at least one cell boundary structurally coupled to the auxetic structures, said auxetic structures having a size greater than about 1 mm, said at least one cell boundary configured to resist a deformation of said auxetic structures, said at least one cell boundary at least partially surrounding the plurality of auxetic structures collectively and including a plurality of connectors extending into the auxetic structures to structurally couple the at least one cell boundary to the auxetic structures.

A method of manufacturing an automotive energy absorber comprising a plurality of auxetic structures and at least one cell boundary structurally coupled to the auxetic structures, said auxetic structures having a size greater than 1 mm, said at least one cell boundary configured to resist a deformation of said auxetic structures, said at least one cell boundary at least partially surrounding the plurality of auxetic structures collectively and including a plurality of connectors extending into the auxetic structures to structurally couple the at least one cell boundary to the auxetic structures, the method comprising:

• extruding a plastic material to form the automotive energy absorber, wherein said extrusion comprises forcing the plastic material through a die, the die comprising a cross section complimentary to the auxetic structures.