Deformation and defects in hydroforming of 5A06 aluminum alloy dome with controllable radial pressure

Abstract

A new process of hydroforming with controllable radial pressure was proposed to overcome difficulties in the forming of low plastic materials and large height-to-diameter ratio workpieces. A typical 5A06 aluminum alloy dome was numerically and experimentally investigated. The reasons for typical defects were analyzed under different radial pressures. Effects of radial pressure on the thickness distribution were discussed and optimal radial pressure was determined. It is shown by numerical simulations and experiment that a cup with a drawing ratio of 2.4 is formed by the new process of hydroforming with controllable radial pressure. It is significantly effective for the forming of low plastic materials and large height-to-diameter ratio workpieces. Two typical thinning points exit along the dome wall. With the radial pressure, thinning is decreased effectively at the two points, the dome forming is achieved and thickness distribution is more uniform.

Keywords

aluminum alloy / hydroforming / radial pressure / fracture / thickness

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