Bruddfasthet

Bruddfasthet is a term used in some Nordic languages, notably Swedish and Norwegian, to describe the fracture resistance of materials—their ability to withstand the formation and growth of cracks under applied loads. It encompasses both crack initiation and crack propagation resistance and is closely related to, but not identical with, general strength or hardness. In English-language literature, the concept is often discussed under fracture toughness or crack-growth resistance, with quantitative measures such as the critical stress intensity factor K_IC or J_IC used to quantify resistance to fracture.

Evaluation of bruddfasthet typically relies on standardized fracture tests, such as compact tension (CT), single-edge notched bending (SENB), or chevron-notched specimens. These tests yield properties that inform design against brittle, quasi-brittle, or ductile fracturing. Bruddfasthet is influenced by microstructure (for example, grain size and phase distribution), the presence of defects or inclusions, residual stresses, temperature, and environmental conditions such as moisture or chemicals.

In engineering practice, bruddfasthet guides safety margins and failure analyses for structural components, pressure vessels, and aerospace parts, and is particularly important for brittle materials like ceramics and for composites where crack growth governs lifetime. The term is common in Scandinavian technical literature, though less so in English-language sources; when translating, bruddfasthet is often rendered as fracture toughness or fracture resistance.

See also: fracture toughness, brittle fracture, crack propagation, materials science.