Elastic Limit| Definition, Formula, and Simple Explanation

Share this post on:

A material’s elastic limit is the maximum distance it can be stretched or distorted before returning to its original shape.
In the area where elastic strain occurs, the slope of the stress-strain curve remains constant. The elastic limit is the point at which applied stress causes an onset of permanent deformation and changes the slope of the stress-strain curve.

In simple words, the elastic limit is the value of applied force beyond which the object does not come back to its original shape when the applied stress is removed.

Hooke’s Law for Elastic Limit

Hooke’s law is important for understanding how a material behaves when stretched or squeezed.
Hooke’s law states that strain is proportionate to applied stress within a material’s elastic limit. When elastic materials are stretched, the atoms and molecules deform until tension is applied, and then they return to their former state when the stress is released.

Types of Deformation

There are two kinds of deformation:
Elastic Deformation: When the stress is removed, the material reverts to its original dimensions before the load was applied. The deformation is reversible and temporary.
Plastic Deformation: This happens when a material is subjected to a great deal of stress. The stress is so great that when it is removed, the material does not return to its original dimensions. There is an irreversible permanent deformation. The elastic limit of a material is the minimal value of stress that causes plastic deformation.

What is Elastic Limit in Physics?

Most materials are elastic up to a point, but the amount of force and the associated deformation within which elastic recovery is possible for any specific material is always limited. The elastic limit is the maximum stress or force per unit area within a solid material that may occur before irreversible deformation begins. Excessive stress beyond the elastic limit causes the material to shatter or be permanently changed. 
The elastic limit indicates the end of elastic behaviour and the beginning of plastic behaviour in materials. 

Elastic Limit in Simple Terms

The elastic limit is a property of materials that describes the maximum amount of stress or force that can be applied to a material without causing it to deform or change shape permanently.

When a material is subjected to stress or force, it will deform, or change shape. At low levels of stress, the deformation is temporary, and the material will return to its original shape once the stress is remove

d. This is called elastic deformation, and the material behaves like a spring.

However, as the stress on the material increases, the deformation becomes permanent, and the material will no longer return to its original shape. This is called plastic deformation, and the material will remain deformed even after the stress is removed.

The point at which the material transitions from elastic deformation to plastic deformation is called the elastic limit. The elastic limit is an important property of materials because it determines the level of stress that the material can withstand without suffering permanent damage.

Materials with a high elastic limit are often used in applications where they will be subjected to high levels of stress or force, such as construction or engineering. It is important to choose materials that have an elastic limit that is higher than the expected stress or force to ensure that the material will not fail or become permanently deformed.

Daily Life Examples of Elastic Limit

Here are some examples of the elastic limit in daily life:

1. Springs in mattresses and other furniture – The springs in mattresses and other furniture are designed to provide support and comfort by absorbing the weight of the person using it. The springs have an elastic limit beyond which they will no longer provide the necessary support and will permanently deform.
2. Rubber bands – Rubber bands are designed to stretch and return to their original shape when released. However, if stretched beyond their elastic limit, they will become permanently stretched and lose their elasticity.
3. Bicycle tires – Bicycle tires are made of elastic materials such as rubber and are designed to withstand the weight of the rider and absorb shocks from bumps in the road. If the tire is overinflated beyond its elastic limit, it may burst or become permanently deformed.
4. Clothing – Clothing made of elastic materials such as spandex or elastane is designed to stretch and return to its original shape when worn. However, if stretched beyond their elastic limit, they will become permanently stretched and lose their elasticity.
5. Springs in cars – Cars have many springs that are used to provide support and absorb shocks. These springs have an elastic limit beyond which they will no longer provide the necessary support and will permanently deform.

Overall, the elastic limit is an important property of materials that determines their ability to withstand stress and deformation without suffering permanent damage. This property is important in many applications, including those we encounter in our daily lives.

Calculating Elastic Limit

Here are the general steps for calculating the elastic limit of a material:

1. Prepare a sample of the material that is representative of the material you want to test. The sample should be free of defects or damage that could affect the results.
2. Apply a known amount of stress to the sample using a mechanical testing machine or other apparatus. The stress can be applied in different ways depending on the type of material and the testing method used. The stress can be gradually increased until the material starts to exhibit permanent deformation.
3. Measure the resulting strain or deformation of the material as the stress is increased. The strain is the amount of deformation that occurs relative to the original size of the material. This can be measured using strain gauges, displacement sensors, or other instruments.
4. Plot the results on a stress-strain curve, which shows how the material responds to stress at different levels of deformation.
5. Determine the point on the stress-strain curve where the material starts to exhibit permanent deformation. This is the elastic limit of the material.

What is the Proportional Limit and how is it different from the Elastic Limit?

The proportionate limit is the point on a stress-strain curve when the linear, elastic deformation area moves into a non-linear, plastic deformation phase. In other words, the proportional limit shows the largest stress that is directly proportional to strain.
The elastic limit is the maximum stress that a material can withstand without undergoing plastic (permanent) deformation. The elastic limit is similar to or almost equivalent to the proportional limit for many materials.

Examples of Elastic Limit

• Elastic Waistband
• Spring Toys
• Spring Mattress
• Trampoline

Related Links

Strain Energy Concept And Formula Derivation

Flexural Strength- An Overview

Metal Definition & Meaning| Simple Explanation

Elastic Potential Energy

What Is Malleability in Metal?

Frequently Asked Questions

1. What is the difference between ductile and brittle materials?

Ductility is a measure of the degree of permanent deformation that can occur before total failure. Ductile materials, such as steel and brass, undergo significant plastic deformation before final breakdown.
Brittle materials, on the other hand, such as glass and concrete, exhibit little or no plastic deformation, and total failure occurs shortly once a threshold value of stress is achieved. As a result, brittle materials do not have a yield point..2

2. What is stress in physics?

In physics, stress is a measurement of the magnitude of the forces that generate deformation. Stress is often defined as force per unit area.

3. What is tensile stress?

Tensile stress is the force that causes objects to pull apart. It is defined as the amount of force applied along an elastic rod divided by its cross-sectional area in a direction perpendicular to the applied force.

4. Yield point definition?

The yield point of material occurs when it transitions from elastic behaviour (in which releasing the applied force restores the material to its original shape) to plastic behaviour (where deformation is permanent).

5. Spring constant?

The spring constant, k, is a measure of the stiffness of the spring. It depends on the spring and the material. The higher the spring constant, the stiffer and harder the spring is to extend.

More Links

Damped Oscillation

Angular Momentum| Rotational Momentum

Carbon Fibre Braided Composite Tubes

Kinetic Energy Formula

Fatigue Testing of Thermoset Composites

Share this post on: