Hardness is a measure of how resistant solid matter is to various kinds of permanent shape change when a force is applied. Macroscopic hardness is generally characterized by strong intermolecular bonds, but the behavior of solid materials under force is complex; therefore, there are different measurements of hardness: scratch hardness, indentation hardness, and rebound hardness.

Hardness is dependent on ductility, elastic stiffness, plasticity, strain, strength, toughness, viscoelasticity, and viscosity.

Common examples of hard matter are ceramics, concrete, certain metals, and superhard materials, which can be contrasted with soft matter.

Read more about Hardness:  Measuring Hardness, Hardening, Physics

Other articles related to "hardness":

Hardness - Physics - Mechanisms and Theory
... The key to understanding the mechanism behind hardness is understanding the metallic microstructure, or the structure and arrangement of the atoms at the atomic level ... at the grain level of the microstructure that are responsible for the hardness of the material ... allowed by these dislocations causes a decrease in the material's hardness ...
Barcol Hardness Test
... The Barcol hardness test characterizes the indentation hardness of materials through the depth of penetration of an indentor, loaded on a material sample ...
Barcol Hardness Test - Barcol Impressor
... by Walter Colman as a hand-held, portable means of assessing the hardness of a material during World War II ... a hand-held method of checking the hardness of rivets due to concerns that aircraft could be sabotaged by replacing normal rivets with soft lead or wooden ones which would ... The hardness of the material determines how far the tip indents and this is transferred by a tension spring and lever to be read on a dial ...
Lattice Problem - Closest Vector Problem (CVP) - Known Results
... showed that any hardness of SVP implies the same hardness for CVP ... strengthened this by giving a NP-hardness result with for ...
Meyer Hardness Test - See Also
... Brinelling Hardness comparison Knoop hardness test Leeb Rebound Hardness Test Rockwell scale Vickers hardness test ...

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