Representation of mechanical behavior in the presence of internal damage

✍ Scribed by E.T. Onat

• Publisher: Elsevier Science
• Year: 1986
• Tongue: English
• Weight: 865 KB
• Volume: 25
• Category: Article
• ISSN: 0013-7944
• DOI: 10.1016/0013-7944(86)90026-3

✦ Synopsis

Deformation of a material is accompanied by changes that take place in its internal structure. These changes exhibit different degrees of permanency. Some of these changes disappear, immediately or slowly, upon unloading; some others (such as dislocation tangles) may need annealing for their removal; others (such as voids on grain boundaries) may be so permanent that we refer to them as internal damage.

The paper is concerned with the representation of the relationship that exists, for a given material and temperature and for small deformations, between histories of applied stress and the observed strain, the accompanying internal happenings and the eventual failure of the material.

In particular the role played by irreducible even rank tensors in the representation of internal structure is discussed and clarified. The restrictions placed by thermodynamics on constitutive equations are considered and the use of potentials in these equations is examined and criticized.