Authors: Ribeka Takahashi David T Fullwood Brent L Adams
Publish Date: 2014/06/11
Volume: 45, Issue: 10, Pages: 4710-4722
Abstract
This study employs a novel stressbased Hybrid–Bishop–Hill yield model approach to evaluate the yield surface of oxygenfree electronic copper samples The local yield surface is determined from three parameters of crystal orientation and one parameter of geometrically necessary dislocation GND All four local state variables can be rapidly determined by analysis of measured electron backscatter diffraction patterns Estimates for the polycrystalline yield surface are obtained by standard averaging procedures The shape of the yield surface is most influenced by the texture of the material while the volume of the envelope scales with the average GND density However correlations between crystal orientation and GND content modify the yield surface shape and size While correlations between GND density and crystal orientation are not strong for most copper samples there are sufficient dependencies to demonstrate the benefits of the detailed fourparameter model The fourparameter approach has potential for improving estimates of elasticyield limit in all polycrystalline materials
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