Disclosed are aluminum alloy hollow materials and processes for producing
the same wherein an aluminum alloy hollow material is produced by subjecting an
ingot of an aluminum alloy containing 0.31.5 wt % Mn to port hole extrusion
or port hole extrusion and drawing-elongation processing and wherein a difference
in electric conductivity between individual portions in lengthwise direction of
the hollow material is not more than 1.0 IACS %. According to the aluminum alloy
hollow materials, preferential corrosion in welding potions in port hole extrusion
can be prevented.
