To provide an aluminum hollow extruded material capable of improving moldability of a welded part and minimizing thickness fluctuation of a molded article after hot forming when a tube expansion forming such as a hot bulging at a high temperature is carried out by integral molding requiring a high tube expansion rate to the aluminum hollow extruded material having the welded part.
The aluminum hollow extruded material having the welded part is used as a material for hot tube expansion forming. At a stage before hot tube expansion working, working with a sectional area reduction ratio(%) of 15% defined by the following formula: the sectional area reduction ratio(%)=[(a sectional area before working-a sectional area after the working)/the sectional area before the working]100 is applied by cold working to at least a part including an area becoming a tube expansion forming part later (a tube expansion forming scheduled part ).
TAGUCHI KAZUO
Toshio Yano
Toshiomi Yamazaki
Takuya Kuno
Kimihiro Hoshi
Hiroyasu Ninomiya
Shuichi Sumiyoshi
Einzel Felix-Reinhard
Takaho Kawawa