Strain Mapping of Al–Mg Alloy with Multi-scale Grain Structure using Digital Image Correlation Method
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Al–Mg alloy powder was mechanically milled in liquid N2 (cryomilling) to produce thermally stable powder with nanocrystalline (NC) microstructure for the manufacture of high-strength alloys. A multi-scale microstructure was achieved by blending unmilled coarse-grained (CG) powder with cryomilled powder and subsequently consolidating. The final bulk alloy was comprised of ultra-fine grained (UFG) regions and discrete CG bands. Dynamic observations of tensile deformation of the alloy were recorded using a micro-straining module attached to a light microscope, and the displacements were measured by digital image correlation (DIC). Strain inhomogeneity between UFG regions and ductile CG bands was observed in the micro-strain (strain order of 10−4–10−6) range, and the strain behavior was interpreted in terms of dislocation plasticity. Special emphasis was given to the distinct displacements between adjoining regions during deformation.
KeywordsDigital image correlation Strain mapping Strain localization Cryomilling Ultrafine grains Bimodal grain structures
- 2.Weertman JR, Averback RS (1996) Mechanical properties. In: Edelstein AS, Cammarata RC (eds) Nanomaterials: synthesis, properties and applications. Institute of Physics Publishing, Bristol, pp 323–345Google Scholar
- 3.Newbery AP, Han BQ, Lavernia EJ, Suryanarayana C, Christodoulou JA (2007) Mechanical alloying and severe plastic deformation. In: Groza JR, Shackelford JF, Lavernia EJ, Powers MT (eds) Materials processing handbook. CRC, Boca Raton, FA, pp 13.1–13.28Google Scholar