Modulus of Elasticity

Definition

The ratio of the unit stress in a material to the corresponding unit strain. The ratio of normal stress to corresponding strain for tensile or compressive stresses below the proportional limit of the material; referred to as "elastic modulus of elasticity"; "Young's modulus," and "Young's modulus of elasticity"; denoted by the symbol E.

Purpose

The modulus of elasticity measures a material's ability to deform elastically (reversibly) under stress. It is a fundamental property used in engineering and materials science to predict how materials will behave under load, ensuring structures are designed to be both safe and functional.

Examples of Use

• Structural engineering: Calculating deflections in beams and columns under load.
• Material selection: Comparing the stiffness of different materials for specific applications.
• Mechanical design: Ensuring components can withstand operational stresses without permanent deformation.

Related Terms

• Stress: The force applied per unit area within materials.
• Strain: The deformation or displacement of material relative to its original length.
• Tensile Strength: The maximum stress that a material can withstand while being stretched or pulled before breaking.

Notes

• The modulus of elasticity is expressed in units of pressure, such as Pascals (Pa) or pounds per square inch (psi).
• Materials with a high modulus of elasticity are stiffer and deform less under stress.
• Understanding the modulus of elasticity helps engineers design structures and components that can safely bear the expected loads.