Measurement and analysis of the strength differential effect of 6000-series aluminum alloy sheet

Measurement and analysis of the strength differential effect of 6000-series aluminum alloy sheet

AKIYAMA Kaisei, KUWABARA Toshihiko

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Abstract. The tension-compression asymmetry (TCA, referred to as the strength differential effect, SDE, for annealed materials) of a 1.1-mm-thick 6000-series aluminum alloy sheet, A6116-T4, which is 3-months age hardened is measured using a uniaxial tensile test and an in-plane compression test. It is found that the in-plane compressive flow stress is 1-7 % higher than the uniaxial tensile flow stress; therefore, the material exhibits the SDE. Moreover, a stacked compression test in the normal (through-thickness) direction (ND) of the test sample is also performed to measure the hydrostatic stress dependence of the yield stress. It is found that the uniaxial compressive flow stress in the ND is 4-9 % higher than the equibiaxial tensile flow stress measured using a cruciform equibiaxial tension test (ISO 16842); therefore, the hydrostatic stress dependence of the yield stress is confirmed. Hence, it is concluded that the SDE observed in A6116-T4 is caused by the hydrostatic stress dependence of the yield stress.

Compressive Flow Stress, Stacked Compression Test, Equibiaxial Tensile Test, Hydrostatic Stress

Published online 4/24/2024, 8 pages
Copyright © 2024 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: AKIYAMA Kaisei, KUWABARA Toshihiko, Measurement and analysis of the strength differential effect of 6000-series aluminum alloy sheet, Materials Research Proceedings, Vol. 41, pp 1115-1122, 2024


The article was published as article 123 of the book Material Forming

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