Finite-Elements Modeling and Simulation of Electrically-Assisted Rotary-Draw Bending Process for 6063 Aluminum Alloy Micro-Tube

Bent micro-tubes have been frequently applied in electronics, medical devices and aerospace for heat transfer due to the increasing heat flux in high-density electric packages. Rotary-draw bending (RDB) is a commonly used process in forming tubes due to its versatility. However, the control of forming defects is the key problem in micro-tube bending in terms of wall thinning, cross-sectional deformation and wrinkling. In this paper, a three-dimensional (3D) finite-elements (FE) modeling of electrically-assisted (EA) RDB of 6063 aluminum alloy micro-tubes is developed with the implicit method in ABAQUS. The multi-field coupled behavior was simulated and analyzed during the EA RDB of micro-tubes. Several process parameters such as micro-tube diameter, bending radius, current density and electrical load path were selected to study their effects on the bending defects of the Al6063 micro-tubes. The simulated results showed that the cross-sectional distortion could be improved when electrical current mainly pass through the vicinity of the tangent point in the micro-tube RDB, and the cross-sectional distortion tended to decrease with the increases of current density and tube diameter, and the decreases of bending speed and radius. A trade-off should be made between the benefit and side effect due to electrical current since the risk of wall thinning and wrinkling may increase.

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Effect of Geometry Parameters on Cross-Sectional Distortion of Thin-Walled Rectangular Tube in Rotary-Draw Bending Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.189-193.2784 ◽

2011 ◽

Vol 189-193 ◽

pp. 2784-2787 ◽

Cited By ~ 2

Author(s):

Yu Li Liu ◽

Gang Yao Zhao ◽

Jin Zhang ◽

He Yang

Keyword(s):

Finite Elements ◽

Geometrical Parameters ◽

Rotary Draw Bending ◽

Deformation Degree ◽

Cross Sectional ◽

Bending Process ◽

Rectangular Tube ◽

Thin Walled ◽

Draw Bending ◽

Finite Elements Model

In rotary-draw bending process of thin-walled rectangular tube, cross-sectional distortion is an unwanted byproduct, which is closely related to geometry parameters. To study the effects of geometry parameters on cross-sectional distortion, a 3-D finite-elements model was built under the ABAQUS/Explicit environment, and its reliability was validated by experiments. Then, simulation and analysis of the influence laws of geometrical parameters on cross-sectional deformation degree were carried out. The results show that increases with the increase of b/h and decreases with the increase of R/h when b/h>1. However, R/h has little influence on δh when b/h≤1. And the influence of b on δh is larger than that of h, and the effect of h on δh is larger than that of R.

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Development of Forming Method for Aluminum Alloy Channel with Curvature and Modified Cross-Section Shape in Rotary Draw Bending

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1110.130 ◽

2015 ◽

Vol 1110 ◽

pp. 130-135

Author(s):

Kosuke Ito ◽

Noah Utsumi ◽

Masashi Yoshida

Keyword(s):

Aluminum Alloy ◽

Cross Sections ◽

Manufacturing Systems ◽

Bend Angle ◽

Secondary Process ◽

Rotary Draw Bending ◽

Cross Sectional ◽

Axial Tension ◽

The Cross ◽

Draw Bending

In the manufacturing industry, metal cross-sections and profiles are manufactured by using extrusion as the primary process. Subsequently, the products are generally subjected to bending in a secondary process. However, long products with the same cross-sections are typically mass-produced by one extrusion. In industries that manufacture such products, there have been increasing demands for flexible manufacturing systems that can be used for low-volume diverse products. However, it is difficult to adapt traditional manufacturing systems to this requirement. In this study, we aimed to develop a new bending method that can be used to deform the cross-sections of existing versatile extruded sections, such as channel materials and rectangular tubes, to several types of cross-sectional shapes and to simultaneously impose a desired curvature on them. The rotary draw bending process for an aluminum alloy channel material without tensile flanges was investigated by using the finite element method and experiments. The effects of the bend angle and thickness ratio on the cross-sectional deformation were examined. Furthermore, the influence of additional axial tension on the channel materials was studied. Additional axial tension can be used to control the outward and inward deformations of the webs. In addition, it was confirmed that the axial tension is very effective in preventing wrinkling and folding.

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