Elastisitetsmodul

Elastisitetsmodul, known in English as the modulus of elasticity or Young's modulus, is a fundamental material property that quantifies the stiffness of a solid material under small deformations. It is defined as the ratio of stress to strain in the linear elastic region of the stress‑strain curve and is expressed mathematically as E = σ/ε, where σ is applied stress and ε is resulting strain. The unit is pascals (Pa) in the International System of Units, often stated in gigapascals (GPa) for engineering steels and other structural materials.

Typical values for common engineering materials include 200 GPa for structural steel, 70 GPa for aluminum alloys, and 3 GPa for most plastics. Biological tissues, such as cortical bone, have values around 18 GPa, while rubber shows values in the megapascal range. These differences highlight how elastisitetsmodul informs the selection of materials for applications ranging from construction to medical implants.

Elastisitetsmodul is determined experimentally via tensile, compression, or bending tests where force–elongation data are recorded. Classical tests (ASTM, ISO) provide standardized procedures for measuring the modulus over a range of temperatures and strain rates. The modulus also appears in analytical solutions for beam bending, shaft torsion, and wave propagation in solids, underscoring its role in both design and fundamental physics.