Patent ID: 6299706
Filing Date: 2001-10-09
Classification: C22F

Abstract:
A process for forming an article formed of a high-strength aluminum alloy, said process comprising the steps of:providing a homogenized aluminum alloy preform having a Vickers hardness Hv of 40 or more;plastic working said preform to increase the Vickers hardness of said preform by at least 20 Hv and to store working energy in said preform; and forming said article by extruding the plastic-worked preform in a porthole extrusion process which includes the steps of:(a) dividing said preform into a plurality of portions; and(b) welding a first of the divided portions of said preform to a second of the divided portions of said preform to form a welded portion, the welding resulting from recrystallization which occurs in a boundary area of the welded portion and is caused by the stored working energy.