Stress and its Types

Stress is the internal force per unit area within a solid material that arises due to the application of external forces or loads.

Formula of Stress

The formula of stress is given below:

Stress (σ) = Force (F) / Area (A)

SI Unit of Stress

  • The SI unit of stress is Pascal (Pa), which is equivalent to Newton per square meter (N/m²).

Dimension of Stress

  • The dimension of stress is [Force] / [Area], which can be expressed as [M][L]⁻²[T]⁻².

Types of Stress

The different types of stress are

  • Tensile Stress
  • Compressive Stress
  • Shear Stress
  • Torsional Stress

They are discussed below in detail

Tensile Stress

The tensile stress, also called elongating stress, is the stress that pulls a material apart. These stresses produce an elongation and decrease in the cross-sectional area of the material. A rope holding a big heavyweight and the stress in the walls of a tank under high pressure are among examples of tensile stress.

Compressive Stress

Squeezing or compressing stress materials can be referred to as compressive stress. The stress results in the material shrinkage and their broadening in the cross-section. For example, the stress in the legs of table legs caused by the weight of the tabletop may be regarded as a compression stress and in the case of a house, we may consider the stress in the walls supporting the floors above as a compression stress as well.

Shear Stress

Shear stress is the stress that causes the adjacent parts of a material to slide in opposing directions. This stress type can lead to the material flattening without any volume change. Webs of an I-beam being subjected to the shear stress is an example in which the flanges are supporting the transverse loads; another example is the shear stress in a building wall that is due to the wind loads.

Torsional Stress

A specific kind of stress, often known as torque or torsional stress, is generated as a result of the awkward twisting or rotational motion of a material. This type of stress can result in the material making a helical patterned deformity. Torsional stress serves as an example of varied stress. It could be the stress on the shaft of a mechanical system that passes power from the motor to the driven machine itself.

Mechanical Properties of Solids

Mechanical properties of solids are key to predicting or explaining their behaviours in response to external force and stress. Such properties enable a solid material to react differently to various kinds of loads e.g. tension, compression, shear, or torsion. Understanding this characteristic is crucial in various areas such as engineering, materials science, and structural design, where the strength and stability of materials are always the first priority.

In this article, we will learn in detail about various mechanical properties of solids and other concepts such as stress, strain, Hooke’s law etc. related to it.

Table of Content

  • What are the Mechanical Properties of Solids?
  • Stress and its Types
  • Strain and its Types
  • Hooke’s Law
  • Stress-Strain Curve
  • Elastic Moduli
  • Poisson’s Ratio

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What are the Mechanical Properties of Solids?

Mechanical properties of solids simply help us observe how a material would potentially respond when an external force or stress is applied to it. It provides information about a material’s solidity, hardness, elasticity, plasticity, and ductility. Knowing these properties can help us decide if a material will be suitable for a task. It also helps us predict its behaviour with varying loads....

Stress and its Types

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Hooke’s law states that stress in a solid is directly proportional to strain if the material is not elongated beyond its elastic limit. This relationship can be expressed mathematically as:...

Stress-Strain Curve

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Conclusion

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