Yield point

Articles elastic limit , yield strength and yield strength overlap thematically. Help me to better differentiate or merge the articles (→ instructions ) . To do this, take part in the relevant redundancy discussion . Please remove this module only after the redundancy has been completely processed and do not forget to include the relevant entry on the redundancy discussion page{{ Done | 1 = ~~~~}}to mark. - Jo hannes Kalliauer^{( e-mail )}_♥ - Discussion | Posts 5:57 PM, Jul 21, 2013 (CEST)

In rheology, the flow limit is the mechanical stress above which a material begins to flow . Loads above the yield point cause permanent plastic deformation . This process is irreversible .

A material remains elastic when cold below the yield point . That is, it will return to its original shape when the load is removed. The deformation is reversible .

After the yield point has been exceeded, the material can deform under a load that increases or even decreases less rapidly. The exact course is described by the flow curve and, for example in the case of tensile stress , the stress-strain diagram . In the case of many materials (e.g. metals ) the so-called expansion hardening occurs with further deformation . The reason is often an increase in the density of dislocations in the crystal structure of the material.

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Tensile stress , one speaks of the yield point or, if the exact onset of flow cannot be precisely determined, of the yield point .
Pressure load , so we used to speak of the crush limit .
Bending , one speaks of the bending limit .
Twist , one speaks of the torsion limit .