The physics of plastic deformation

doi:10.1016/0749-6419(87)90021-0

International Journal of Plasticity

Volume 3, Issue 3, 1987, Pages 211-247

Dedicated to the Memory of Aris Phillips^∗

https://doi.org/10.1016/0749-6419(87)90021-0 Get rights and content

Abstract

A simplified physical picture is extracted from the many complicated processes occuring during plastic deformation. It is based upon a set of continuously distributed straight edge dislocations, the carriers of plastic deformation, moving along their slip plane, interacting with each other and the lattice, multiplying and annihilating. The principles of continuum physics, that is the conservation laws of mass and momentum, and results from discrete dislocation modelling are then employed to analyze the situation and deduce a closed set of relations describing the evolution of deformation and the associated forces that bring it about. A simple method is suggested for extending these relations to macroscales. This way, current phenomenological models of plasticity are physically substantiated. Moreover, a framework is provided for rigorously constructing small and large deformation theories of plasticity. Finally, a new possibility is made available for capturing the salient features of the heteogeneity of plastic flow including the wavelength of persistent slip bands, the width of shear bands, and the velocity of Portevin-Le Chatelier bands.

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^∗: It is an honor and pleasure to have given the opportunity to dedicate this article to Aris Phillips, not only because through his own research he set a permanent example for young scientists, in general, but also because he was a constant supporter of my earlier work on the mechanics and physics of diffusion in solids, in particular. In line with the great Greek tradition, he was an advocate of geometry, but he did not fail to recognize the importance of the analysis of the physical processes that bring geometric changes about. In fact, at the time that the majority of the mechanics journals showed hesitation towards new approaches to stress-asisted diffusion, environmental fracture and dislocation-based plasticity theories, Phillips' ”Acta Mechanica” became a vehicle for the dissemination of such ideas and helped their growth and maturity.

View full text

The physics of plastic deformation

Abstract

J. Mech. Phys. Solids

Mech. Mater.

Mech. Mater.

Int. J. Engng. Sci.

Int. J. Engng. Sci.

Int. J. Engng. Sci.

Mater. Sci. Eng.

Soil Mechanics and Plastic Analysis or Limit Design

Quart. Appl. Math.

Strain Bursts and Coarse Slip During Cyclic Deformation

Z. Metallkd.

Micromechanics of Flow in Solids

Anisotropy in Plastic Torsion

J. Basic Engng.

Crystal Dislocations and the Theory of Elasticity

Elementary Physicochemical Degradation Processes

On the Perfect Lattice-Dislocated State Interaction

Cyclic Plasticity of Matrix and Persistent Slip Bands in Fatigued Metals

On a Proposal for a Continuum with Microstructure

Acta Mechanica