The modified Dugdale-Barenblatt model adapted to various fracture configurations in metals

The modified Dugdale-Barenblatt model adapted to various fracture configurations in metals

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Title

The modified Dugdale-Barenblatt model adapted to various fracture configurations in metals (EN)

Creator

Gdoutos, EE (EN)

Theocaris, PS (EN)

Type

journalArticle (EN)

Partial document
Publication in journal (EN)

Article
Scientific article (EN)

Issued

2014-03-01T01:05:31Z

1974 (EN)

Year

1974 (EN)

Description

The Dugdale-Barenblatt model is extended to encompass the influence of strain hardening on the plastic enclaves developed at the tips of a crack in a plate subjected to tension at infinity. While in the DB-model the distribution of internal stresses along the plastic zone in the extension of the crack length was taken constant and equal to the yield stress, in the modified version of this model this distribution is taken variable with a minimum value the yield stress (σ0) and a maximum value (σmax depending on the loading step and the amount of strain-hardening of the material. Six different configurations of stress distribution in the plastic enclaves were considered with various values of the ratio σmax/σ0. For each stress configuration and for various loading steps the shape of the respective caustic corresponding to the singularity created at the plastic zone near the crack tip was computed by modifying appropriately Dugdale's theory to each of the six configurations in the plastic enclave. The caustic was formed by reflections of a parallel coherent light beam at the vicinity of the crack-tip. Three different types of steel were examined with different stress-strain relations and different amounts of strain-hardening. By comparing the shapes of the theoretically derived caustics by using each of the stress configurations of the modified DB-model with the shapes of the experimentally obtained caustics for the corresponding loading step it was possible to adapt the DB-model to each case of material, to disclose the influence of strain-hardening on the fracture mode of the material and to indicate the most probable profile of stress distribution in the plastic zone as the loading is increased and further plastic deformation is established in the specimen. Interesting results have been revealed on the influence of strain hardening in the fracture mode of metals. © 1974 Noordhoff International Publishing. (EN)

Scientific field

Mechanics (EN)

Engineering and Technology
Mechanical Engineering (EN)

Subject

Internal Stress (EN)

Stress Distribution (EN)

Model Adaptation (EN)

STRAIN HARDENING (EN)

METALS AND ALLOYS (EN)

Yield Stress (EN)

PLATES - Failure (EN)

Strain Hardening (EN)