Investigation on the effect of Equal-Channel Angular Pressing process on the pure copper grain size

Year 2015, Volume: 36 Issue: 3, 239 - 247, 13.05.2015

Mohammad Javad Bagheri , Payam Saraeıan

Abstract

Abstract. Severe plastic deformation is a general concept for the explanation of a group of metal-working methods that apply many strains without changing the overall dimensions of the work piece. In other words, due to the special geometry of tools, the deformation of tools is restrained which applying this process will prevent the flow of materials, thus, creating enormous hydrostatic pressure. This pressure along with high shear strain results in high-density defects in the crystal lattice, leading to the formation of fine grains. The method of pressurizing under angular channels with identical cross sections (extrusion in angled cross section channels) is a suitable process for producing a material with fine structure, high strength, and desired physical properties. The aim of this research is to show that by decreasing the grain size of copper, its strength is increased. It was understood that the ECAP process appropriately decreased the grain size of the widely used metal, and in the eighth repeated test, reached the grain size number 11 14 falling into the standards of ASTM, which is equal to 2 – 8 micrometers.

Keywords

ECAP, Pure copper, Grain size

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