Bulge forming for Al-Mg series aluminum alloy hollow extruded material

摘要

PROBLEM TO BE SOLVED: To provide an Al-Mg based aluminum alloy hollow extrusion material for bulging which has excellent formability.;SOLUTION: This Al-Mg based aluminum alloy hollow extrusion material contains, by mass, 1.5 to 5.0% Mg, and 0.005 to 0.2% Ti. If required, the aluminum alloy contains one or more metals selected from 0.05 to 1.0% Mn, 0.05 to 0.3% Cr, 0.05 to 0.2% Zr and 0.01 to 0.2% V. The mean axial ratio between the major axis and the minor axis of crystal grains in the center part of the sheet thickness is ≤4.5, and the mean crystal grain diameter of recrystallized grains to 500 μm from the outer surface is ≤500 μm. The extrusion material is suitable as an automobile suspension subframe having a complicated shape.;COPYRIGHT: (C)2003,JPO