Investigation of thickness variation and corner filling in tube hydroforming

Tube hydroforming is a near-net shape metal forming process in which a straight or a pre-bent tubular blank is placed in a closed die cavity and its cross-sectional shape is changed using internal hydraulic pressure that forces the tube to conform to the shape of the die cavity. This paper reports on the results of two-dimensional plane-strain finite element models of the tube hydroforming process, which were conducted using the commercial finite element code ABAQUS/Standard. The objective of the study is to examine the interaction of material properties and die geometry on the selection of hydroforming process parameters. The paper discusses the effects of the strain-hardening exponent, initial tube wall thickness, and die corner radii on corner filling and thickness distribution of the hydroformed tube.