Potential of the KOBO extrusion process for nonferrous metals in the form of solids and chips

Abstract

AbstractThe research undertaken for this paper was inspired by the results of theoretical analyzes and strong experimental evidence confirming the possibility to induce the phenomenon of viscous flow (typical for liquids) in the process of low-temperature KOBO extrusion of metals. Thus, despite the constant solid state of the metal, the KOBO plastic deformation process requires much lower stress (low flow resistance) in comparison with conventional extrusion. On the other hand, the KOBO method is particularly attractive due to the generation of high strength properties in the product/extrudate favorable for low (room) temperature deformation as well as superplastic features at higher temperature ranges.This paper presents the results of the studies on the efficiency of low-temperature KOBO extrusion of hardly-deformable materials in massive form (Mg4Li, AK11, Cu6.5P) and fragmented fractions (2014, 7075, AZ91, titanium grade 2). Particular attention was paid to the structure and mechanical properties of the obtained extrudates, which were rated as exceedingly favorable. As such, the paper provides new technological arguments for the application of the KOBO method in plastic deformation of materials as it guarantees their functional properties.