Investigation of Microstructure and Mechanical Properties of ETP Copper Deformed by Equal Channel Angular Pressing (ECAP)

Abstract

Severe plastic deformation (SPD), the plastic deformation of materials under high pressure, is used to improve the mechanical and structural properties of materials. Equal Channel Angular Pressing (ECAP) is one of these methods used to produce materials microstructure with submicron or nano-sized grains by applying high pressure to the sample passing through two angular intersecting channels with the same diameters. In recent years, studies on the production of nano-grained metallic materials have increased. The aim of this study is to examine the gradual change of the microstructure and mechanical properties of the material under high pressure and to determine the effect of ECAP on the improvement of these properties. This process is directly related to the internal structure and texture of the material. With the applied method, it is aimed to obtain a more durable material structure. Electrolytic Tough Pitch (ETP) copper material, which is one of the copper types commonly used in electrical applications, was chosen in the study. 12 mm diameter and 35 mm long ETP copper samples, which were not subjected to any heat treatment, processed on 2 mm/s pressing speed, 200°C mold temperature and Bc ECAP route using a 120 ton capacity hydraulic press, a precision machined mold which has 120° (Φ=120°, ψ=20°) channel angle. The changes in the crystal structure, microstructure and mechanical properties of the ECAP applied samples were investigated. According to the data obtained, it was observed that the 4 passes of ECAP application resulted in having finer grains in microstructure and improvement in mechanical properties.