strain component

Strain is a measure of relative deformation in materials subjected to applied forces. It quantifies the change in shape and size of elastic, plastic, and fluid materials as their constituent particles are displaced.1

There are two primary types of strain:
* Normal Strain: Caused by forces perpendicular to a material's cross-sectional area. This occurs in materials under pressure or when a rod is stretched or compressed lengthwise. For volume changes, it's the change in volume divided by the original volume. For length changes, it's the change in length divided by the original length. Tensile strains are positive, and compressive strains are negative.1
* Shear Strain: Caused by forces parallel to a material's cross-sectional area, like twisting a metal tube. This deforms right angles within the material, changing them from 90 degrees. The shear strain is the tangent of the angle change.1

Strain is a dimensionless quantity. It is closely related to stress, which is the force per unit area within a material. Hooke's Law states that for small deformations, stress is directly proportional to strain. Temperature changes can also induce strain, known as thermal strain, which is proportional to the temperature change and the material's coefficient of thermal expansion.23