کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1447979 | 988661 | 2010 | 15 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Room-temperature equal channel angular extrusion of pure magnesium Room-temperature equal channel angular extrusion of pure magnesium](/preview/png/1447979.png)
In this paper, we demonstrate a way to impart severe plastic deformation to magnesium at room temperature to produce ultrafine grain size of ∼250 nm through equal channel angular extrusion (ECAE). The strategy to deform magnesium at lower temperature or to achieve such grain sizes has been proposed as: (i) to obtain a suitable initial orientation with high Schmid factor for basal slip and low Schmid factor for pyramidal/prismatic slip; (ii) to take advantage of low stacking fault energy of basal and high stacking fault energies of prismatic/pyramidal planes in order to relatively work-harden the basal plane with respect to the pyramidal/prismatic plane; and (iii) to lower the temperature of deformation in steps, leading to continual refinement of grains, resulting in finer grain size. The experimental as well as simulated texture of ECAE-processed samples indicate that the deformation mechanism leading to ultrafine grain size is slip-dominated. The recrystallization mechanism during ECAE has been found to be orientation-dependent.
Journal: Acta Materialia - Volume 58, Issue 9, May 2010, Pages 3247–3261