METAL FLOW DURING EXTRUSION OF NON-CIRCULAR SECTIONS

Abstract

The paper presents the analysis of nature of metal flow during extrusion of non-circular sections and determining the relationship between extrusion force and geometrical parameters of extrudate (the shape of the extrudate). Experimental procedure was curried out for the simplest cases of non-circular profiles (triangle, square, rectangular) of various geometrical parameters. The extrusion load and punch displacement have been registered during experimental work. By determining parameters of metal plastic flow (the depth of plastic zone Lp and the dead zone angle sm) it has been shown the difference in nature of metal flow during extrusion product differing in non-circular sections. This differentiation results in the complex nature of flow consequential from change with circular section of the billet to non-circular section of extrudate.
It has been shown that flow resistance can be different with regard to appearing configurations of deformation zones (the size and shape of plastic zone, dead and shear zones) and dependent from for example geometrical parameters of a die (shape and size of an die orifice).