Micrograph 710 and full record
- Micrograph no
- Brief description
- Wrought-grade aluminium alloy (Al-Mg-Fe-Si containing < 1wt.% of each solute); refined with TiB2 particles. Deformation of grain structure is due to cutting of sample with scissors.
- alloy , aluminium , anodising , deformation, equiaxed , iron, magnesium, metal, silicon
- Metal or alloy
- Not specified
- Standard codes
- Deformed by cutting with scissors.
- Sample preparation
- Electrolytically etched using Barker's reagent.
- Cross-polarised light microscopy
- Length bar
- 400 μm
- Further information
- This micrograph illustrates the effect of deformation on a previously equiaxed structure. Strain causes the elongation of grains and the subsequent anodising produces 'mottled' grain colours; the oxide layer is not of constant orientation or thickness across a grain.
The Barker's etch and applied electrical field produce a thick oxide layer on the grains of aluminium (anodising). When viewed in cross-polarised light, interference in the oxide layer produces colours which depend on grain orientation and oxide thickness; hence the grain structure is imaged.
- T Quested
- Department of Materials Science and Metallurgy, University of Cambridge
- Licence for re-use
- Attribution-Non-Commercial-Share Alike 2.0 UK: England & Wales
- Related micrographs
- Micrograph 711: As-cast wrought-grade aluminium alloy (Al-Mg-Fe-Si containing < 1wt.% of each solute). No addition of grain refinement particles (e.g. TiB2). (1 mm)
- Micrograph 712: As-cast wrought-grade aluminium alloy (Al-Mg-Fe-Si containing < 1wt.% of each solute). Addition of TiB2 particles facilitates the formation of a fine, equiaxed grain structure (grain refinement). (400 μm)
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