Texture dependent strain rate sensitivity of ultrafine-grained aluminum films

• DOI: 10.1016/j.scriptamat.2015.12.003
• Publication Date: 2015-12-17T13:53:39Z
• Authors: Ehsan Izadi; Jagannathan Rajag...
• Keywords: Texture (cosmology); Flow stress; Strain (injury)

Abstract We investigated the strain rate sensitivity (SRS) of freestanding ultrafine-grained aluminum films with similar thickness (~ 240 nm) and mean grain size (~ 275 nm) but highly dissimilar texture. For (110) textured bicrystalline films, flow stress increased by 14% ( m = 0.017) as the strain rate was varied from ~ 7 × 10 − 6 /s to 5 × 10 − 3 /s. In contrast, for non-textured films the flow stress increased by more than 90% ( m = 0.103) over a similar strain rate range. The drastic difference in SRS can be explained by texture-induced changes in deformation mechanisms of the films, as revealed by in situ TEM straining experiments.