Plasticity

of these articles describes a material property. For the sport-scientific meaning see plasticity to flow (sport

) by plasticity understands one the characteristic of solid materials under an application of force to deform () and this form after the effect maintain. In contrast to it a flexible material became its originalForm again take and a brittle material with immediate failure react - one speaks of brittle failure (ceramic(s), cubic-body-centered metals at low temperatures). Both break and plastic deformation are always connected with flexible deformation.

The plastic deformation behavior hangs among other things of the tensile state,the temperature, the type of load and the rate of load application off. Thus one knows the high temperature plasticity, creep deformation and superelasticity apart from the conventional plasticity also.

Microscopically the plastic deformation is described by crystalline solids (metals) on the basis the transfer theory. For energetic reasons it is more favorable, individual defects(Transfers) to float by the solid body, instead of moving all atomic rows at the same time. Generally the comparison to a large, long carpet , is consulted here which one wants to move around a piece. It would cost enormously much Kraft to pull the whole carpet at one time - instead ofits can pass one a small fold through easy. (see also firmness)

a further model for the description of the plasticity comes from E. C. Bingham.

Examples:

High plasticity:

  • Already
  • knead tooth paste , Majonäse or butter can one with low pressure on the tube or with thatMeasurers soften and to flowing bring.
  • One can bend a thin metal wire into any form.
  • With very high pressure will ice plastic and can as glaciers flow.
  • With still higher pressures will rock salt likewise plastic and can salt plugs and even salt glaciers form.

Small plasticity:

  • Glass breaks without itself to deform before.
  • A rubber band is very flexible, however always maintains its original form.

See also: Ductility

literature

  • E. C. Bingham, Fluidity and Plasticity. New York, McGraw Hill, 1922
  • A. H. Cottrell, these locations and plastic flow inCrystals. Clarendon pressing, 1953
  • W. F. Hosford, The mechanic OF crystals and textured polycrystals. Oxford University press, 1993

other term meanings

  1. of the neuro sciences is located synaptic plasticity for aktivations or development-development change of the transmission strength of a synapse.
 

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