Aluminum extrusion material for hydraulic bulge forming and hydraulic bulge forming method using the extrusion material

Abstract

An aluminum extrusion material for hydraulic bulge forming, which can produce hydraulic bulge forming components possessing highly reliable and sufficient strength and rigidity capable of withstanding not only a static load, but also a twist load and dynamic load is provided. Also provided is a hydraulic bulge forming method using the aluminum extrusion material for hydraulic bulge forming as a raw material. The aluminum extrusion material is hollow and used as a material for hydraulic bulge forming. The material is characterized by having a partition wall radially crossing the hollow part of the extrusion material, wherein the partition wall is provided with an allowance in length to become flat when the hollow part is formed into a prescribed shape by hydraulic bulge forming.

What is claimed is:  
     
         1 . A hollow aluminum extrusion material for hydraulic bulge forming characterized by having a partition wall radially crossing the hollow part of the extrusion material, wherein the partition wall is provided with an allowance in length to become flat when the hollow part is formed into a prescribed shape by hydraulic bulge forming.  
     
     
         2 . The hollow aluminum extrusion material for hydraulic bulge forming of  claim 1 , wherein the partition wall has a thickness of 0.5-1.5 times the thickness of the peripheral wall of the hollow aluminum extrusion material.  
     
     
         3 . The hydraulic bulge forming method characterized by feeding a fluid to the hollow part of the aluminum extrusion material for hydraulic bulge forming of  claim 1  or  claim 2 , used as a raw material, applying pressure to the fluid to form the peripheral wall of the extrusion material in a desired shape, and, at the same time, flattening the partition wall.