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چکیده
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A severe plastic deformation (SPD) technique, namely constrained groove pressing (CGP), is employed to investigate its influence on the texture and mechanical properties of AZ91D magnesium sheets.Three cycles of CGP process were conducted on the AZ91Dannealed sheets at elevated temperature. Optical microscopy,scanning electron microscopy, and X-ray diffraction (XRD) were used to characterize microstructural evolutions. Hardness and tensile tests at room temperature were performed to determine the mechanical properties. The microscopy observations showed that β-Mg17Al12 particles existed in the annealed sample. The average grain size (AGS) was reduced from 18 µm to 14 µm after the first CGP cycle. Also, the basal texture of the annealed sample was controlled during the first CGP cycle. The yield strength and elongation of the annealed sheet (129.4 MPa, 24.5%) were respectively increased to 166.7 MPa and 36.1%, by performing just the first pass of the CGP operation. The inverse pole figures showed that the main texture direction was [0 0 0 1]║TD. Afterward, it was found that 3-passed worksheet had the lowest homogeneity with a maximum inhomogeneity factor of 5.69.
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