US Patent 8,277,719 (October 2, 2012), "Process for the Preparation of
Auxetic Foams," Andrew Alderson, Kim Lesley Alderson, Philip John Davies, and Gillian Mary Smart (
Auxetic Technologies Ltd., Great Britain).
Presentations will consider composites and magnesium plate, the use of carbon nanotubes and ceramics, the ballistic performance of titanium, multifunctional uses of
auxetic materials, the European Defence Agency's European protective individual defence armour project, and a systematic approach to armour development using Triz.
Auxetic materials [1, 2] are those which when stretched expand rather than contract in width.
Patent 7,858,055 (December 28, 2010), "Moisture Sensitive
Auxetic Material," WanDuk Lee, SangSoo Lee, CholWoh Koh, and Jin Heo (Kimberly-Clark Worldwide, Inc., Neenah, Wisconsin, USA).
Synthetic
auxetic materials have been fabricated since 1987 [1] when Lakes produced a polymeric foam with a negative Poisson's ratio, [nu].
Auxetic materials laterally expand under uniaxial tension or laterally shrink under uniaxial compression.
Recent publications have detailed how
auxetic (negative Poisson's ratio) polymers have been fabricated by a novel thermal processing route consisting of three well-defined stages--compaction, sintering and extrusion.
A highly fibrillar
auxetic form of ultra-high molecular weight polyethylene (UHMWPE) has been fabricated by using a powder processing route comprising two stages--sintering and extrusion.
Subsequently, the range of synthetic materials capable of existing in
auxetic forms has included polymer gels (2), molecular structures (3), and microporous polymers (4-6).
Auxetic materials have a negative Poisson's ratio when stretched becoming thicker in a direction perpendicular to the direction of the applied force.