3003 铝合金双层盒形壳体液压成形工艺及壁厚控制

To solve the problem of cracking in deep drawing of aluminum alloy box part with double-layer shell, the composite forming process of sheet hydroforming and hydraulic bulging of box part was proposed. The effects of blank holder force, chamber pressure and bulging pressure on wrinking and cracking of box part with double-layer shell were studied, and the key process parameters were optimized. The results show that the sheet hydroforming process is helpful to improve the wall thickness distribution, and the reasonable chamber pressure can reduce the wall thickness thinning of the inner and outer sheets, but the excessive chamber pressure can lead to the excess of the initial back expansion of the sheet, leading to the further thinning and even the rupture of the sheet. Under a certain bulging pressure, the outer sheet can be formed to stick the die. The effect of composite process on the forming of aluminum alloy box part with double-layer shell was studied by experiment. The maximum wall thickness thinning rate is less than 15%. The composite process provides a new method for forming aluminum alloy box parts with double-layer shell.