Microstructure of Ultrafine- Grained Metals after Ecap

This paper was aimed at verification of functionality of the ECAP technology at extrusion of the copper, alluminium alloys and steel. Experiments were made on equipment, which is demonstrated in the Fig 1. Deformation forces were measured during extrusion, resistance to deformation was calculated and deformation speed was determined approximately. Analysis of structure was made with use of light microscopy and TEM. The samples of Cu and Al alloys were extruded at room temperature. For the samples of steel was used the two-stage pressing, when the samples were extruded at temperature of approx. T1 = 325 C and T2 = 220 C. In order to increase concentration of deformation in volume of the sample the samples were after individual passes turned around their longitudinal axis by 90 o and they were extruded again. Cross-section of original samples of Cu and Al alloys was 8 x 8 mm and their length was 32 mm and cross-section of original samples of Fe alloy was 10 x 10 mm and their length was 40 mm .