The property of certain materials that enables them to return to their original dimensions after an applied stress has been removed. In general, if a stress is applied to a wire, the strain will increase in proportion (see OA on the illustration) until a certain point called the limit of proportionality is reached. This is in accordance with Hooke's law. Thereafter there is at first a slight increase in strain with increased load until a point L is reached. This is the elastic limit ; up to this point the deformation of the specimen is elastic, i.e. when the stress is removed the specimen returns to its original length. Beyond the point L there is permanent deformation when the stress is removed, i.e. the material has ceased to be elastic and has become plastic . In the plastic stages individual materials vary somewhat; in general, however, at a point B there is a sudden increase in strain with further increases of stress — this is the yield point . Beyond the point C, the breaking stress , the wire will snap (which occurs at point D).
Elasticity
- fractal
- fractional quantum Hall effect
- frame of reference
- Franklin, Benjamin
- Frasch process
- Fraunhofer diffraction
- Fraunhofer lines
- Fraunhofer, Josef von
- free electron theory
- free energy
- free fall
- free space
- freeze drying
- freezing mixture
- Frenkel defect
- Frenkel-Kontorowa model
- frequency
- frequency modulation
- fresnel
- Fresnel diffraction
- Fresnel lens
- friction
- froth flotation
- frustum
- fuel