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1

Evolution of Goss texture in an Al–Cu–Mg alloy during cold rolling

Zhao Qi, Liu Zhiyi, Hu Yangcheng, Li Shasha, Bai Song

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 1

340--354

EN

Evolution of Goss texture in an Al–Cu–Mg alloy during cold rolling was investigated by three-dimensional orientation distribution functions, electron back-scattered diffraction and transmission electron microscopy. The results showed that with increasing reduction from 23.7 to 80%, Goss textures gradually transformed into Brass texture through the activation of sole {111}<110> slip systems. When rolling reduction further increased from 80 to 86.3%, Goss texture rather than Brass started to rotate towards Copper and S components. The formation of Copper and S textures at these high reductions was attributed to the activation of {110}<110> and {001}<110> non-octahedral slip systems.

2

Effect of texture on deformation mode in magnesium and AZ61 alloy

Sułkowski B.

Metallurgy and Foundry Engineering

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2018

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Vol. 44, no. 2

91--100

EN

The effect of the initial texture on the deformation mode and mechanical properties was studied in magnesium and its AZ61 alloy. Both materials had a very similar initial texture. Two cases were investigated: samples with a texture where the basal slip system was blocked, and samples having a texture where the basal slip system was allowed to activate. The samples were deformed by compression at room temperature at a strain rate of 10−3 s−1. It was found that the initial texture had a very strong impact on the deformation mode in magnesium; however, there was no effect of the initial texture on the deformation mode in the case of AZ61. The investigations were compared to simulations of texture evolution using the Taylor model. From the simulations, the Taylor factor and slip system activity were obtained. It was found that, in the case of magnesium, twinning or slip (both basal and non-basal) are the two main deformation modes, while in the case of AZ61, slip is the only main deformation mechanism despite the initial texture. The impact of the initial texture is discussed in more detail in the present study.

PL

W pracy badano wpływ początkowej tekstury na mechanizmy deformacji i właściwości mechaniczne magnezu i stopu magnezu AZ61. Zbadano dwa przypadki: próbki, w których bazalny system poślizgu został zablokowany, oraz próbki, w których bazalny system poślizgu mógł być aktywowany. Próbki odkształcano przez ściskanie w temperaturze pokojowej z prędkością odkształcania 10-3 s-1. Stwierdzono, że początkowa tekstura miała bardzo silny wpływ na sposób deformacji magnezu; jednak w przypadku AZ61 nie zauważono podobnego efektu wpływu początkowej tekstury na właściwości mechaniczne. Badania porównano z symulacjami ewolucji tekstury za pomocą modelu Taylora. Z symulacji uzyskano współczynnik Taylora i aktywności systemów poślizgu. Stwierdzono, że w przypadku magnezu, w zależności od początkowej tekstury, poślizg (zarówno w bazalnym systemie, jak i niebazalnych systemach poślizgu) oraz bliźniakowanie są dwoma głównymi mechanizmami deformacji, natomiast w przypadku AZ61 głównym mechanizmem deformacji, pomimo początkowej tekstury, jest tylko poślizg.

3

The Voigt bound of the stress potential of isotropic viscoplastic FCC polycrystals

Bohlke T.

Archives of Mechanics

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2004

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Vol. 56, nr 6

425-445

EN

The Voigt bound of the stress potential of face-centered cubic (fcc) polycrystals without texture is numerically determined for all types of strain rate states. The numerical findings reveal the dependence of the stress potential on both the second and the third principal invariant of the strain rate deviator. The dependence on the determinant vanishes only for a linear viscoplastic behavior. Due to the dependence of the stress potential on the third principal invariant, the determinant, the viscoplastic flow is generally nonproportional to the stress deviator. A simple analytical expression is found, which reproduces the numerical findings over the full range of strain rate sensitivities.