What is Stress strain curve?

Stress strain curve is a graphical representation of the relationship between stress and strain in a material. It is commonly used to characterize the mechanical behavior of materials and is essential in fields such as materials science, engineering, and physics.

The stress strain curve is typically obtained through a tensile test, where a specimen of the material is subjected to an increasing axial load (tensile force) until it reaches failure.

stages in stress strain curve in obtained through tensile test

During the test, the applied load and the resulting deformation (strain) are measured.

The stress (σ) is defined as the force (F) applied to the specimen divided by the cross-sectional area (A) of the specimen:

σ = F / A

The strain (ε) is defined as the change in length (∆L) of the specimen divided by its original length (L):

ε = ∆L / L

stress strain curve

What is stress according to stress strain curve :  

Stress refers to the internal force or load experienced by a material or structure when subjected to external forces or loads. It is a measure of the intensity of the internal forces within the material that develops in response to the applied external forces.

Stress can be further categorized into different types based on the nature of the forces and the resulting deformations in the material:

1. Tensile Stress: 

Tensile stress occurs when forces act to stretch or elongate a material. It is represented by a force per unit area and is typically measured in units of force per square area (such as pascals or pounds per square inch).

2. Compressive Stress: 

Compressive stress is the opposite of tensile stress and occurs when forces act to compress or shorten a material. Like tensile stress, it is expressed as a force per unit area.

3. Shear Stress: 

Shear stress arises when forces act parallel to the surface of a material, causing one layer of the material to slide or deform relative to adjacent layers. It is also measured in units of force per unit area.