Tensile Stress

Tensile Stress

When an external force is applied to a body then at each cross section of the body an internal restoring force is setup which tends to restore the body to its original state. The restoring setup inside the body per unit area is known as stress. The normal stresses can be either tensile or compressive whether the stresses act out of the area or into the area.

Basically, three different types of stresses can be identified. These are related to the nature of the deforming force applied on the body. That is, whether they are tensile, compressive or shearing.

What is Tensile Stress?

If the deforming force or applied force results in the increase in the object’s length then the resulting stress is termed as tensile stress. For example: When a rod or wire is stretched by pulling it with equal and opposite forces at both ends.

Consider a uniform bar of cross-sectional area A subjected to an axial tensile force P. The stress at any section x – x normal to the line of action of the tensile force P is specifically called tensile stress (Pt). Since internal resistance R at x – x is equal to the applied force P, we have:

Tensile Stress

\(Tensile\,\,Stress{{\left( P \right)}_{t}}=\frac{Internal\,\,resis\tan ce\,\,at\,\,x-x}{\operatorname{Re}sisting\,\,area\,\,at\,\,x-x}=\frac{R}{A}=\frac{Applie\,\,Force(P)}{Cross\,\,\operatorname{Sec}tional\,\,Area(A)}\).

Under tensile stress the bas suffers stretching or elongation. Tensile stress causes stress corrosion cracking, which is the combined influence of tensile stress and a corrosive environment. The required tensile stresses may be in the form of directly applied stresses or in the form of residual stresses.