The elastic materials are materials which have the ability to resist an influence or distort or deform the force, and then return to its original shape and the same size when force is removed. Linear elasticity is widely used in the design and analysis of structures such as beams, sheets and sheets. Elastic materials are of great importance to society, as many of them are used to make clothes, tires, automotive spare parts, etc. Elastic material examples

Characteristics of elastic materials

When an elastic material is deformed by an external force, it experiences an internal resistance to deformation and restores it to its original state if the external force is no longer applied.

To some extent, most solid materials exhibit elastic behavior, but there is a limit to the magnitude of force and deformation that accompanies elastic recovery.

A material is considered elastic if it can be stretched to 300% of its original length.

For this reason, there is an elastic limit, which is the greatest force or stress per unit area of ​​a solid material that can withstand permanent deformation.

For these materials, the elastic limit marks the end of their elastic behavior and the beginning of their plastic behavior. For weaker materials, stress or stress above the yield point results in fractures.

The elastic limit depends on the type of solid considered. For example, a metal bar can be stretched elastically to 1% of its original length.

However, fragments of certain gummy materials can be extended up to 1000%. The elastic properties of most intentional solids tend to fall between these two extremes.

You might be interested. How do you synthesize an elastic material?

Types of elastic materials

Cauchy type elastic material models

In physics, an elastic Cauchy material is one in which the stress / stress of each point is determined only by the current state of deformation with respect to an arbitrary reference configuration. This type of material is also called a simple elastic material. Elastic material examples

From this definition, the stress in a simple elastic material does not depend on the deformation path, the deformation history or the time required to obtain this deformation.

This definition also implies that the constitutive equations are spatially local. This means that stress is only affected by the state of deformations in a neighborhood close to the point in question.

It also implies that a body’s force (such as gravity) and inertial forces cannot affect material properties.

Simple elastic materials are mathematical abstractions and no real material fits this definition perfectly.

However, many elastic materials of practical interest, such as iron, plastic, wood and concrete, can be considered simple elastic materials for stress analysis purposes.

Although the stress of simple elastic materials depends only on the state of deformation, the work performed by stress/strain may depend on the deformation path.

Therefore, a simple elastic material has a non-conservative structure and stress cannot be derived from an elastic function on a potential scale. In this sense, conservative materials are called hyperelastic. Elastic material examples

Hypoelastic materials

These elastic materials are those that have a constitutive equation independent of the finite stress measurements, except in the linear case.

Hypoelastic material models are different from hyperelastic materials or simple elastic material models in that, except in particular circumstances, they cannot be derived from a strain energy density function (FDED).

A hypoelastic material can be rigorously defined as one that is modeled using a constitutive equation that satisfies these two criteria:

• The stress tensor ò time t depends only on the order in which the body held its previous settings, but not during the period in which these previous settings were crossed.

As a special case, this criterion includes a simple elastic material, in which the current tension depends only on the current configuration and not the history of previous configurations.

• There is a function tensor with a value of G, so that ô = G ( ô , L ) where ô is the range of the material stress stress and L is the space velocity gradient tensor.

Hyperplastic materials

These materials are also called green elastic materials. They are a kind of constitutive equation for ideally elastic materials for which the stress relationship is derived from a strain energy density function. These materials are a special case of simple elastic materials.

For many materials, linear elastic models do not correctly describe the observed behavior of the material. Elastic material examples

Hyperelasticity provides a way to model the stress-strain behavior of these materials.

The behavior of empty and vulcanized elastomers often makes up the hyperelastic ideal. Filled elastomers, polymeric foams and biological tissues are also modeled with hyperelastic idealization in mind.

Hyperplastic material models are regularly used to represent large strain behavior in materials.

They are often used to model mechanical behavior and empty and complete elastomers.

Examples of elastic materials

1- Natural rubber

2- Elastane or Lycra

3- Butyl rubber (GDP)

4- Fluoroelastomer

5- Elastomers

6- Ethylene-propylene rubber (EPR)

7- Resin

8- Styrene-butadiene rubber (SBR) 

9- Chloroprene

10- Elastin

11- Rubber epichlorohydrin

12- Nylon

Nylon13- Terpene

14- Isoprene rubber Elastic material examples

15- Polybutadiene

16- Nitrile rubber

17- Stretchable vinyl

18- Thermoplastic elastomer

19- Silicone rubber

20- Ethylene-propylene-diene rubber (EPDM)

21- Ethyl vinyl acetate (EVA rubber or foam)

22- Halogenated butyl rubbers (CIIR, BIIR)

23- Neoprene Elastic material examples