METHOD FOR MANUFACTURING ALUMINUM ALLOY SHEET SUPERIOR IN BENDABILITY

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing an Al alloy sheet which is a 6,000 series aluminum alloy sheet having an anisotropic texture and further having excellent ridging mark resistance. SOLUTION: This manufacturing method comprises the steps of: homogenization-heating an ingot of a 6,000 series aluminum alloy having a particular composition at a temperature between 500°C and the melting point; cooling the ingot to a temperature of 300 to 400°C at a cooling velocity of 50°C/hr or higher; starting hot rolling; finishing the hot rolling at a temperature of 280°C or lower; cold-rolling the plate at a rolling reduction of 10 to 80%; then intermediate-annealing the sheet at 160 to 240°C; further cold-rolling it at a rolling reduction of 15% or higher; then solution-treating and quenching the sheet. Thus obtained aluminum alloy sheet acquires the anisotropy of the texture in which earing ratios in 0°and -90°directions are in a range of -13 to -17%, and has crystal grains with an average grain size of 50μm or smaller. COPYRIGHT: (C)2008,JPO&INPIT