Fracture modelling of DP780 sheets using a hybrid experimental-numerical method and two-dimensional digital image correlation. (1st January 2014)

• Record Type: Journal Article
• Authors: Pack, Keunhwan; Ahn, Kwanghyun; Huh, Hoon; Lou, Yanshan
• Is Part Of: International journal of material & product technology. Volume 48:Number 1-4(2014)
• Page Start: 34
• Page End: 46
• Publication Date: 2014-01-01
• Subjects: ductile fracture -- hybrid experimental-numerical method -- digital image correlation -- DIC -- fracture locus -- fracture forming limit diagram; Manufacturing processes -- Periodicals; Materials -- Testing -- Periodicals; 620.11
• Languages: English
• ISSNs: 0268-1900

Abstract

This paper is concerned with the construction of fracture envelopes of DP780 sheets using two methods: a hybrid experimental-numerical method; two-dimensional digital image correlation (2D-DIC). For the hybrid method, four types of ductile fracture tests were carried out covering a wide range of stress states on specimens: with a central hole; two symmetric circular notches; flat grooved; and diagonally double-notched. Based on the fracture strain and loading paths identified with finite element simulation, a fracture envelope was obtained by employing the three-parameter modified Mohr-Coulomb fracture model. In addition, the fracture surface strain was directly measured using 2D-DIC. Loading histories of each test were extracted from a surface element of a three dimensional finite element model. The comparison of fracture envelopes constructed by the two methods reveals that there is little difference. Thus, it can be concluded that 2D-DIC is applicable to fracture modelling of DP780 sheets despite the assumption of the plane stress condition even after necking.