The Coalescence of Voids in Prestrained Notched Round Copper Bars
Abstract:Notched round copper bars are prestrained to various extents, recrystallized, and finally strained until fracture. Void nucleation and growth during prestraining cause a decrease in the macroscopic void coalescence strain. Modelling of this experiment requires a proper account of the changes in void sizes and their interdistances during prestraining. Modelling based on the Gurson–Leblond–Perrin model for void growth and the Thomason model for void coalescence is proposed. Comparison with experimental results allows a demonstration of the validity of the Thomason model and the inadequacy of models based on a critical porosity value. Porosity at coalescence is found to depend on the initial void volume fraction, the flow properties and the stress state.
Document Type: Research Article
Affiliations: Université catholique de Louvain, Département des sciences des matériaux et procédés, PCIM, place Sainte Barbe 2, B-1348 Louvain-la-Neuve, Belgium
Publication date: 1998-12-01