Theory of Plasticity

Abstract

In the previous discussions of elasticity theory, it was assumed that the mechanical response of the solid was such that all strains vanished with the vanishing of all externally applied disturbances. From simple experiments on certain solids, particularly structural metals, it has, however, been found that this purely elastic response breaks down at some critical stress level and that the recoverable small elastic deformations are then accompanied by plastic deformations which remain present after all external disturbances vanish. In an effort to understand this phenomenon of plastic distortion, we accordingly consider the theory of plasticity in the present chapter, regarding it—as in the case of thermal elasticity and viscous elasticity— primarily as a supplement to the theory of elasticity described in Chapter 4.