Localized Necking in a Round Tensile Bar with HCP Material Considering Tension-Compression Asymmetry in Plastic Flow

Abstract:

In spite of this progress in predicting ductile failure, the development of macroscopic yield criteria for describing damage evolution in HCP (hexagonal close-packed) materials remains a challenge. HCP materials display strength differential effects (i.e., different behavior in tension versus compression) in the plastic response due to twinning. Cazacu and Stewart [1] developed an analytic yield criterion for a porous material containing randomly distributed spherical voids in an isotropic, incompressible matrix that displays tension-compression asymmetry. The matrix material was taken to obey the isotropic form of the Cazacu et al. [2] yield criterion, which captures the tension-compression asymmetry of the matrix material. In this paper, finite element calculations of a round tensile bar are conducted with the material behavior described by the Cazacu and Stewart [1] yield criterion. The goal of these calculations is to investigate the effect of the tension-compression asymmetry on the necking induced by void evolution and propagation.

• Periodical: Key Engineering Materials (Volumes 535-536)
• Pages: 164-167
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.535-536.164
• Online since: January 2013
• Authors: Jonghun Yoon, Oana Cazacu, Jung Hwan Lee
• Keywords: Necking, Round Tensile Bar, Tension-Compression Asymmetry, Void Growth, Void Volume Fraction

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