Effect of Continuous Extrusion Parameters on Alloy M1 Round Section Bar Microstructure and Mechanical Property Formation

Results are provided for microstructural evolution and mechanical property formation in a deformation zone during continuous extrusion, and the effect of extrusion rate parameters on the properties of M1 grade copper rods is also evaluated. The study is conducted on butt-ends and bars obtained in a Conform 350 industrial unit. Investigation of metal flow in the deformation zone shows that features of structure transformation are retained for all specimens. A cast (undeformed) billet has a structure with a large grain size (80–1000 μm). As a result of extrusion a workpiece structure grain size is reduced to 50–35 μm. Quantitative data are obtained for the formation of finished product hardness in relation to equipment configuration and extrusion parameters. Samples extruded at a rate of 6 m/min have an optimum hardness level (62.5 kgf/mm 2 ) that satisfies the standard specifications, unlike other samples extruded at a slower rate.