A car that dashes against an obstacle suffer damage, first to its fenders. To be useful, materials need to maintain a constant Poisson ratio under pressure when they crumble under pressure. However, they are prone not to do so, and the Poisson ratio varies as they deform. There is a keen interest to develop materials that can be sandwiched in the fender system which will absorb the shock and prevent the interiors from being damaged. Origami metamaterials that crumple rather than tear, and take the impact, can play an important role in such situations.
What is Metamaterials?
Metamaterials are nano-engineered media with designed properties beyond those available in nature with applications in all aspects of materials science. A metamaterial is any material engineered to have a property that is not found in naturally occurring materials. They are made from assemblies of multiple elements fashioned from composite materials such as metals and plastics. Some examples of available metamaterials are negative-index metamaterials, chiral metamaterials, plasmonic metamaterials, photonic metamaterials, etc.
What is Origami Metamaterials?
Origami Metamaterials combine the Japanese art of paper folding (origami) and the existing material of choice and fold it to obtain desired properties. Researchers of IIT Madras have developed a special class of origami metamaterials that show a constant value of Poisson Ratio when subjected to stress. These are manufactured by joining panels along their edges to form ‘creases’ about which the structure locally ‘folds’ or rotates about. The benefit is that the observed property does not depend on whether it is made from a sheet of paper, polymer, or metal. The material the researchers have developed has a nearly constant Poisson function in the range –of 0.5 to 1.2 over a finite stretch of up to 3.0 with a minimum of 1.1.
Properties of Metamaterials
They are smart materials that have a wide range of properties and can be so different from each other that there isn’t a definition for them. Some of the properties it possess are
- Unusual Electromagnetic Properties
- Negative Refractive Index
- Acoustic Control
- Negative Electrical Permittivity
- Magnetic Permeability
- Artificial Origin.
Application of Metamaterials
Metamaterials hold attention due to various applications it can provide. Some of its application includes
- Optical Filtering
- Medical Devices
- Remote Aerospace Operations
- Sensor Detectors
- Solar Power Management
- Antenna Lenses
Origami metamaterials can provide a platform for the design of systems with a wide range of thermal expansion coefficients. Experiments and simulations are combined to demonstrate that by tuning the geometrical parameters of the origami structure and the arrangement of plates and creases, an extremely broad range of thermal expansion coefficients can be obtained that will provide a wide variety of applications.