dilatancy

physics

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June 25, 2026

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Dilatancy is the property of a material to increase in viscosity and solidify when subjected to deformation, pressure, or agitation. This phenomenon is related to the verb "dilate," which means to enlarge or widen.123

A dilatant material, when subjected to stress, will resist flow and become more solid. This is the opposite of a Newtonian fluid, which maintains a constant viscosity regardless of stress. Examples of dilatant behavior can be observed in substances like cornstarch and water mixtures, which feel liquid when handled gently but become solid when punched or squeezed.2

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earthquake
Observation and interpretation of precursory phenomena
The theory of dilatancy (that is, an increase in volume) of rock prior to rupture once occupied a central position in discussions of premonitory phenomena of earthquakes, but it now receives less support. It is based on the observation that many solids exhibit dilatancy during deformation. For earthquake…
Read More
The theory of dilatancy (that is, an increase in volume) of rock prior to rupture once occupied a central position in discussions of premonitory phenomena of earthquakes, but it now receives less support. It is based on the observation that many solids exhibit dilatancy during deformation. For earthquake…
Read More