Structure and properties of copper deformed by severe plastic deformation methods

Purpose: The main object of this study is to establish the influence of severe plastic deformation on the microstructure evolution and properties of polycrystalline copper Cu99.99. Design/methodology/approach: Polycrystalline copper Cu99.99 was deformed by cyclic extrusion compression (CEC), equal channel angular pressing (ECAP) and hydrostatic extrusion (HE). Additionally the combination of these methods were applying to the sample deformations. The microstructure and properties of samples after different kinds of severe mode of deformations (SPD) were examined and compared as well as their properties. The microstructure was investigated by optical (MO) and transmission electron microscopy (TEM). The microhardness was measured by PMT3 microhardness tester. Findings: It was found that increase of deformation diminishing the microstructure and leads to the increase of microhardness of samples. Practical implications: The results may be utilized for determination of a relation between microstructure and properties of the copper deformed in the severe plastic deformation process. Originality/value: The results contribute to evaluation properties of the polycrystalline copper deformed to very large strains exerting the typical range of deformations.