Effect of Die Entry Angle on Extrusion Responses of Aluminum 6063 Alloy

Mechanical properties response of extruded 6063 aluminum alloy at varied die entry angle has been investigated. Plain carbon and tool steel dies with entry angles of 15, 30, 45, 60, 75 and 90 were simulated. Extrusion on the alloy was done at ambient temperature (37C) and the extruded samples from the various angles were subjected to selected service related mechanical tests and microstructural analysis. Results show that maximum extrusion pressure and extrudate hardness increase with increasing die entry angle. Contribution to extrusion pressure increase may have come from obtuse changes in the extrudates’ crystal slip system in relation to extrusion direction. Improved deformation was observed in plain carbon steel die in the order 45, 90 and 75 entry angles. However, maximum lateral deformation index of 2.1 was observed with the plain carbon steel die at 45 entry angle against 1.8 of tool steel die. The disparity in the lateral deformation index was attributed to varied responses along longitudinal elongation on load application.