Publication
Title
Ductile crack propagation by plastic collapse of the intervoid ligaments
Author
Abstract
In the present study ductile crack initiation and propagation is investigated by means of a micro-mechanical model under small-scale yielding conditions. Voids are resolved discretely in the fracture process zone where steep gradients occur during the loading history and are taken into accounted by a homogenized porous plasticity law elsewhere. The size of the region of discrete voids is not set a priori but is determined consistently. The results show that effective crack growth occurs by plastic collapse, i.e. purely geometric softening of the intervoid ligaments without incorporating material separation. Due to this mechanism a limit load exists coinciding with the maximum fracture toughness. In addition, it turns out that the shielding due to the growth of voids around the crack plane has a considerable influence on the computed R-curves compared to models neglecting this effect. Depending on the void arrangement a diffuse softening zone or even crack branching is observed. A comparison with experimental data from literature indicates that plastic collapse and the formation of diffuse zones of void growth are realistic mechanisms of ductile crack propagation.
Language
English
Source (journal)
International journal of fracture. - Leiden
Publication
Leiden : 2012
ISSN
0376-9429
Volume/pages
176:1(2012), p. 81-96
ISI
000305222900007
Full text (Publisher's DOI)
UAntwerpen
Faculty/Department
Project info
Publication type
Subject
External links
Web of Science
Record
Identification
Creation 10.02.2015
Last edited 12.12.2017