Abstract
Formability in magnesium alloy sheet is strongly limited by a strong basal texture in the as-rolled material, which is difficulty to remove by thermal processing. We introduce a new process to the control of texture by combining Thixomolding and Thermomechanical Processing (TTMP). Plates of AZ61L with a divorced β-Mg17Al12 eutectic are produced by Thixomolding, resulting in a non-textured, fine grained (2.8 µm) precursor. Sheet produced from the plate by single pass warm-rolling exhibits a weaker texture, and more isotropic tensile deformation than generally observed in AZ-series alloy sheet. Recrystallization annealing produces a further reduction in texture and average grain size (2.3 µm) and results in nearly isotropic room temperature deformation, a yield strength of ~ 220 MPa, and an elongation of ~ 23%. Particle stimulated nucleation of new grains by the β-phase during both dynamic and static recrystallization, is critical for achieving the low levels of texture. The influence of β-phase distribution in microstructure development is discussed.
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© 2013 TMS (The Minerals, Metals & Materials Society)
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Berman, T.D. et al. (2013). Microstructure Characterization of Weakly Textured and Fine Grained AZ61 Sheet. In: Hort, N., Mathaudhu, S.N., Neelameggham, N.R., Alderman, M. (eds) Magnesium Technology 2013. Springer, Cham. https://doi.org/10.1007/978-3-319-48150-0_19
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DOI: https://doi.org/10.1007/978-3-319-48150-0_19
Publisher Name: Springer, Cham
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