Processing of Copper by Equal Channel Angular Pressing (ECAP) – Microstructure Investigations

Abstract:

The present study attempts to apply Equal-Channel Angular Pressing (ECAP) to 99.99% pure copper. ECAP process was realized at room temperature for 4, 8 and 16 passes through route B_C using a die having angle of 90^°. The microstructure of the samples was investigated by means both light and transmission electron microscopy. Additionally the microhardness was measured and statistical analysis of the grains and subgrains was performed. Based on Kikuchi diffraction patterns misorientation was determined. There were some different types of bands in the microstructure after deformation. The shear bands, bands and in the submicron range the microshear bands and microbands are a characteristic feature of the microstructure of copper. Also characteristic was increasing of the number of bands with increasing of deformation and mutually crossing of the bands. The intersection of a bands and microbands leads to the formation of new grains with the large misorientation angle. The measured grain/subgrain size show, that the grain size is maintained at a similar level after each stage of deformation and is equal to d = 0.25 – 0.32 μm.

• Periodical: Key Engineering Materials (Volume 641)
• Pages: 286-293
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.641.286
• Online since: April 2015
• Authors: Beata Leszczyńska-Madej*, Maria W. Richert, Agnieszka Hotloś, Jacek Skiba
• Keywords: ECAP, Microstructure Characterization, Severe Plastic Deformation, Ultra-Fine Grained Copper

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