Predicting the bending limit of AA8112 tubes using necking criterion in manufacturing of bent tubes

Abstract

Nowadays, thin-walled tube bending at small bending ratios is a production process widely used in advanced industries. This research has been carried out to obtain the smallest bending ratio, and maximum applicable internal pressure in Hydro-rotary draw bending of thin-walled AA8112 alloy tube using necking criterion. To accomplish the objective, equivalent plastic strain of extrados critical region has been selected for necking criterion. The results showed that the selected necking criterion would be able to successfully determine the onset of rupture in bending. In order to validate FE simulation, the effects of bending ratio and internal pressure on defects, such as cross-section ovality and thickness changing, have also been investigated through simulation in ABAQUS software and experiments.

Structural model and dynamic analysis of six-axis Cartesian coordinate robot for sheet metal bending

“…Elyasi et al obtained the smallest bending ratio, and maximum-applicable internal pressure in hydro-rotary draw bending of thin-walled AA8112 alloy tube using necking criterion. 12 To solve the problems such as non-uniform wall thickness, large springback, poor fatigue performance, Kong proposed a novel hydro-forming approach to manufacture some thin-walled elbow parts with small bending radius. 13 Phanitwong et al proposed the model of a Z-shaped bending process of sheet metals and studied elastic recovery characteristics of bent parts upon load release.…”