Background: Body, vehicle and other types of armor rely on strength and density to prevent energy transfer from shock or stress. Shock wave and impact forces have traditionally been dealt with through the use of metal, polymer, elastic air cushioned voids, and, in the case of military armor, additional ceramic materials and composites with air voids.
While heavy combat vehicles employ air voids and ceramic
composites to absorb and redirect some of the energy, other materials are
constructed metal or polymers using linear lattice structures, which easily
propagate shock waves. This linear lattice allows shock waves to propagate out
from the contact site in an even hemispherical radiation of the force through
the material. Constant linear lattice site construction allows the energy to
follow these straight continuous lines through the structure until all of the
force is expended in a straight linear fashion through the material medium
usually resulting in plastic deformation of the structure. This energy follows
the lattice structure, disrupting the lattice structure as it propagates, and
it may eventually punch through the structure.
Technology: Adaptive Multiphase Materials (AMM) created at Georgia Tech provide the ability to redirect the linear track of shock energy through selected pathways as it propagates from the impact site. AMMs can be constructed to react to shock and vibration by using non-linear lattice structures. The material can be made to increase the deflection path length to dissipate energy or allow it to be channeled into a desired zone or location. AAMs can be engineered to reverse the direction of the shock wave by using a reflecting lattice structure. It can be formulated to produce reactions to incoming energy waves, resulting in a canceling effect, which can reduce or eliminate vibration or shock wave propagation through the structure.
Potential Commercial Application: Protective armor made from AMMs would be lighter than materials used in secondary armor, light vehicle armor, protective body armor, and products such as sports helmets and sports body wear. Shock from high impact sports can be channeled away from the wearer or reduced or eliminated by shock wave phase cancellation. Structures can be produced from AMMs to reduce vibration penetration from high ambient sound or mechanical vibration. The applications are endless.
· Advanced materials and techniques that bring new applications for impact force resistance and shock wave propagation management
· Provide the ability to redirect stress, shock, and vibration into desired directions or pathways
· Can be constructed to reduce or illuminate shock or vibration through reactive force interference effects
· Wide applications in light weight armor, heavy armor reinforcement, law enforcement or military body armor, high impact sports head and body protection, and vibration reduction or elimination
Dr. Massimo Ruzzene, Dr. Julian Rimoli, Filippo Casadei from the school of Aerospace Engineering at Georgia Tech