Optical Properties of Plastically Deformed Copper

Pure copper (99.99), prepared in the sample of square cross-section (10 × 10 $mm^{2}$) and length about 50 mm, was extremely plastically deformed with the repeated application of Equal Channel Angular Pressing (ECAP). ECAP was applied as an effective technique for producing bulk nano-scaled structures. Optical properties of the sample were investigated using Raman spectroscopy. Two types of lines: narrow (with width of ≈ 7 $cm^{-1}$) and wide ( ≈ 40 $cm^{-1}$) are registered. Existence of two types of lines indicates that in the specimen exists nano-sized crystal structures of both Cu and CuO related with three dimensional amorphous boundary spaces, which indicates that plastic deformation of the sample did not lead to total amorphisation of the specimen.