hardhetskvantifikasjoner

Hardness quantity (Swedish: hårdhetskvantitet) is a physical measure used to express the resistance of a material to permanent deformation, typically by indentation, scratching, or abrasion. It is not a single intrinsic material property but a category of related quantities that depend on test method, scale, and conditions. Common hardness quantities include Mohs hardness (scratch resistance), Vickers and Knoop hardness (microindentation), Brinell hardness (macroscopic indentation), and Rockwell hardness (depth-sensing indentation). Each produces a numerical value tied to a specific procedure and indenter geometry.

Measurement procedures specify load, indenter type, contact time, and surface preparation; values are reported with the test method (for example, HV for Vickers, HB for Brinell, HR for Rockwell). Hardness correlates with other mechanical properties such as tensile strength and wear resistance, but these relationships are empirical and material-dependent. Conversions between scales use standardized charts or empirical equations but can be approximate, especially across different material classes.

Applications of hardness quantities span metallurgy, ceramics, polymers, and coatings, where they inform quality control, material selection, and failure analysis. Limitations include sensitivity to surface condition, indentation size effects, and anisotropy in textured or composite materials. Appropriate interpretation requires knowledge of the testing method and the material system under study.