Biaxial deformation in high purity aluminum

Journal Article · Fri Sep 25 00:00:00 EDT 2015 · Materials Science and Engineering. A, Structural Materials: Properties, Microstructure and Processing

DOI: https://doi.org/10.1016/j.msea.2015.09.086 · OSTI ID:1304709

Livescu, V. ^[1]; Bingert, J. F. ^[2]; Liu, C. ^[1]; Lovato, M. L. ^[1]; Patterson, B. M. ^[1]

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1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2. Office of the Under Secretary of Defense for Acquisition, Technology and Logistics, Washington, DC (United States)

The convergence of multiple characterization tools has been applied to investigate the relationship of microstructure on damage evolution in high purity aluminum. The extremely coarse grain size of the disc-shaped sample provided a quasi-two dimensional structure from which the location of surface-measured features could be inferred. In particular, the role of pre-existing defects on damage growth was accessible due to the presence of casting porosity in the aluminum. Micro tomography, electron backscatter diffraction, and digital image correlation were applied to interrogate the sample in three dimensions. Recently micro-bulge testing apparatus was used to deform the pre-characterized disc of aluminum in biaxial tension, and related analysis techniques were applied to map local strain fields. Subsequent post-mortem characterization of the failed sample was performed to correlate structure to damaged regions. We determined that strain localization and associated damage was most strongly correlated with grain boundary intersections and plastic anisotropy gradients between grains. Pre-existing voids played less of an apparent role than was perhaps initially expected. Finally, these combined techniques provide insight to the mechanism of damage initiation, propagation, and failure, along with a test bed for predictive damage models incorporating anisotropic microstructural effects.

• Research Organization: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE
• Grant/Contract Number: AC52-06NA25396
• OSTI ID: 1304709
• Report Number(s): LA-UR--15-25320
• Journal Information: Materials Science and Engineering. A, Structural Materials: Properties, Microstructure and Processing, Journal Name: Materials Science and Engineering. A, Structural Materials: Properties, Microstructure and Processing Journal Issue: C Vol. 648; ISSN 0921-5093
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English