Abstract
In this work, the mode I fracture response of a rolled Mg AZ31 alloy is investigated by conducting experiments using notched compact tension specimens. It is found that the notched fracture toughness J c ∼ 42 N/mm which is moderately high. Detailed examination using EBSD and optical metallography indicates that profuse tensile twinning occurs almost over the entire uncracked ligament ahead of the notch root. This leads to considerable hardening as evidenced by slope of the load versus displacement curve and toughness enhancement by plastic dissipation. Strong texture changes are also observed near the extended crack tip. The fracture morphology involves dimpling at the specimen mid-plane and shear lip formation close to the free surfaces. The fracture resistance of the Mg alloy is discussed in the context of the above observations.
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Narla, S.P., Narasimhan, R., Suwas, S. (2015). Role of Tensile Twinning on Fracture Behavior of Magnesium AZ31 Alloy. In: Manuel, M.V., Singh, A., Alderman, M., Neelameggham, N.R. (eds) Magnesium Technology 2015. Springer, Cham. https://doi.org/10.1007/978-3-319-48185-2_28
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DOI: https://doi.org/10.1007/978-3-319-48185-2_28
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