Abstract
The formability of four Mg AZ31B sheets produced by either direct chill or twin roll continuous casting, and having different initial grain sizes, was investigated at 400 °C and 5x10−3 s−1 using the pneumatic stretching test. Blanks were pneumatically bulged through four elliptical die inserts, with aspect ratios ranging between 1.0 and 0.4, producing ellipsoidal domes with different biaxial strain combinations. Testing was carried out in two ways: with the major strains being aligned either along or across the rolling direction of the material. Strain combinations were measured in the deformed specimens, and the forming limit curves were constructed for each of the four sheets in two orientations. The results show great impact of sheet orientation on material formability limits. Additionally, the results reveal significant differences between the four sheets; those differences were correlated back to disparities in grain structure and material inhomogeneities.
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© 2012 TMS (The Minerals, Metals & Materials Society)
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Abu-Farha, F., Verma, R., Hector, L.G. (2012). Hot Formability Curves for Four AZ31B Magnesium Alloy Sheets Obtained by the Pneumatic Stretching Test. In: Mathaudhu, S.N., Sillekens, W.H., Neelameggham, N.R., Hort, N. (eds) Magnesium Technology 2012. Springer, Cham. https://doi.org/10.1007/978-3-319-48203-3_53
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DOI: https://doi.org/10.1007/978-3-319-48203-3_53
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