ALUMINUM EXTRUDED MATERIAL FOR HYDROFORMING AND METHOD OF MANUFACTURING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a port hole extruded material which makes pipe expansion forming equal to that of a mandrel extruded material of an aluminum hollow extruded material for hydroforming and a method of manufacturing the same. SOLUTION: The aluminum hollow extruded material by port hole extrusion which is the blank of hydroforming is characterized in that the average crystal grain sizes (the diameters in terms of complete roundness) of the perform section and welded section of the extruded material are both below 100μm and the difference between the average crystal grain sizes of the perform section and welded section of the extruded material is below 10μm. The aluminum extruded material is manufactured by subjecting the material to port hole extruding then to cold working of a reduction ratio of >=10%.