Numerical Investigation, Prediction and Comparison of Ductile, Shear and MSFLD Damage Model in Cross-Shape Tube Hydro-Forming Process

Hamidreza Alinaghian Elyaderani¹ Hossein Ghazavi²

1) 1. Department of Mechanical Engineering, Amir Kabir University, Tehran, Iran
2) 2. Department of Mechanical Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran

Publication : International Congress on Science, engineering & New Technologies(secongress.com/1st)
Abstract :
The tube hydro-forming process consists of the simultaneous or sequenced application of an axial compression as well as an internal pressure (transmitted by a fluid medium, e.g. water) into a cavity or hollow part in order to produce tubular parts with different transversal sections. It s a manufacture process used mainly for the automobile and aeronautical industries for the manufacturing of low-cost parts, with reduced weight and bigger structural integrity when compared with conventional metal forming processes. Currently two techniques of hydro-forming are distinguished: the hydro-forming with sequenced pressurization, PSH (pressure sequence hydro-forming) and the hydro-forming under high pressure, HPH (high-pressure hydro-forming). Both the techniques had been developed to facilitate the forming process of more complex parts preventing problems of wrinkling, buckling and rupture. A three-dimensional finite element simulation, based on the rigid–plastic model for the analysis and design of hydro-forming process was developed. The hydraulic pressure force is applied to the normal direction of the tube work piece by integrating the pressure with respect to each element’s surface area. The predicted simulation results provide information on the actual design. This numerical approach to the hydro-forming process will be useful to the development and application for a wide range of automobile structural components. In this paper, 3D models of hydro-forming has been simulated by finite element method. Three damage model, coupled with von Mises plastic criterion, have been applied to predict where and when onset of ductile, shear and MSFLD rupture occur. Also, 3D models of hydro-forming has been simulated to study the deformation of blank, distribution of stress contours and contour of equivalent plastic strain in process. All studies presented in this paper have been carried out on aluminum alloy EN AW-7108 T6.
Keywords : Hydro-Forming Numerical Investigation Cross Shape Tube Ductile Fracture Criteria Shear Fracture Criteria MSFLD Fracture Criteria Aluminum Alloy EN AW-7108-T6