7000 SERIES ALUMINUM ALLOY EXTRUDED MATERIAL WITH EXCELLENT STRENGTH, EXTRUSION PROPERTY AND GLOSS

摘要

The present invention relates to a 7000 series aluminum alloy which is an Al-Zn-Mg-(Cu) based thermally treated aluminum alloy and, more specifically, relates to a 7000 series aluminum alloy with excellent strength, extrusion property, and gloss which improves extrusion productivity and does not easily generate deformation or flaw when the extruded material of the present invention is manufactured as a frame of a mobile communication terminal such as a smartphone or an electronic device like a digital camera having high gloss as yield strength and extrusion property and gloss of the extruded material of the present invention have highly improved when compared to a prior 7000 series aluminum alloy. The present invention provides the 7000 series aluminum alloy extruded material with excellent strength, extrusion property, and gloss which shows an extrusion speed equal to or greater than 4 mm/sec when an aluminum billet comprises: 0.2 wt% or less of Si, 0.4 wt% or less of Fe, 0.3-1.2 wt% of Cu, 1.0-2.0 wt% of Mg, 0.3-0.9 wt% of Mn, 5.1-6.1 wt% of Zn, 0.19-0.25 wt% of Cr, 0.02 wt% or less of Ti, 0.14-0.25 wt% of Zr; and the remaining consisting of Al preheated at a temperature of 400-500°C and then extruded, having a yield strength equal to or greater than 492 MPa when heat treatment is performed to maintain the extruded aluminum billet for five hours at 100°C and then for eight hours at 150°C through a temperature rising process for 30 minutes, and then cooling the aluminum billet and having a gloss of 135-170 gloss unit (GU) after anodizing.;COPYRIGHT KIPO 2016