Coupling digital image correlation and finite element analysis to determine constitutive parameters in necking tensile specimens. (15th October 2016)

• Record Type: Journal Article
• Authors: Gerbig, Daniel; Bower, Allan; Savic, Vesna; Hector, Louis G.
• Is Part Of: International journal of solids and structures. Volume 97/98(2016)
• Page Start: 496
• Page End: 509
• Publication Date: 2016-10-15
• Subjects: Digital image correlation -- Finite element -- Inverse modelling -- Constitutive behavior -- Viscoplastic response; Mechanics, Applied -- Periodicals; Structural analysis (Engineering) -- Periodicals; Elastic solids -- Periodicals; Mécanique appliquée -- Périodiques; Constructions, Théorie des -- Périodiques; Solides élastiques -- Périodiques; Elastic solids; Mechanics, Applied; Structural analysis (Engineering); Periodicals; 624.18
• DOI: 10.1016/j.ijsolstr.2016.06.038
• Languages: English
• ISSNs: 0020-7683

Abstract

Abstract: A general framework is described for coupling digital image correlation (DIC) with finite element analysis to determine material parameters from measurements of nonuniform displacement fields in a specimen. The approach is to minimize the difference between measured and computed displacement fields and external forces applied to the specimen by repeatedly correcting the material parameters in a chosen constitutive model. The minimization can be accomplished analytically, and the resulting nonlinear system of equations solved using a Newton–Raphson procedure that integrates naturally with standard nonlinear finite element computations. As a representative application, the method is applied to measure the flow behavior of tensile specimens beyond uniform elongation. The results of a series of tensile tests on tapered HSLA 590FB steel specimens show that the effective stress-strain behavior can reliably be extracted to a strain of 60%, well beyond the limits of 20% commonly achieved using traditional engineering analyses on straight-gauge specimens. Highlights: Analytically combines digital image correlation and finite element analysis. Applicable to arbitrary constitutive model. Tested and verified with simulated tensile experiments. Applied to measure flow behavior beyond 60% strain from necking tensile experiments.