HIGH-STRENGTH AND HIGH-DUCTILITY AL ALLOY AND PROCESS FOR PRODUCTION OF THE SAME

摘要

The invention aims at providing an Al-Zn-Mg-Cu 7000-series aluminum alloy which exhibits high ductility for its high strength. In order to attain the aim, an Al-Zn-Mg-Cu 7000-series aluminum alloy having an inclusion-free structure is produced by reducing the oxygen content of an Al alloy obtained by rapidly solidifying a molten Al-Zn-Mg-Cu 7000-series aluminum alloy into a perform with an inert gas, preferably by spray forming. The aluminum alloy of the invention has a tensile strength of 600MPa or above as one of the mechanical characteristics at ordinary temperature and exhibits an elongation of 15% or above when the tensile strength is 600 MPa or above but below 800MPa and an elongation of 10% or above when the tensile strength is 800MPa or above, being excellent in cold workability such as rollability.