Nonlinear Finite Element Analysis of Barge Collision with a Single Bridge Pier

Patient-specific simulations of stenting procedures in coronary bifurcations: Two clinical cases

Tube hydroforming process: A reference guide

Finite elements in the analysis of pressure vessels and piping, an addendum: A bibliography (2001–2004)

Forming limit diagrams with the existence of through-thickness normal stress

Bursting is an irrecoverable failure mode in tube hydroforming, in contrast with buckling and wrinkling. To predict bursting failure in the hydroforming processes, Oyane's ductile fracture criterion is introduced and evaluated from the results of stress and strain productions obtained from finite element analysis. The region of fracture initiation and the bursting pressures are predicted and compared with a series of experimental results. It is shown that the material parameters used in the criterion can be obtained from the forming limit diagram. From the simulation results of tube bulging, the prediction of the bursting failure based on the ductile fracture criterion was demonstrated to be reasonable. This approach can be extended to a wide range of practical tube hydroforming processes.

A prediction of bursting failure in tube hydroforming processes based on ductile fracture criterion

An automobile lower arm has been fabricated in a prototype form by hydroforming with the aids of numerical analysis and experiments. For the numerical process design, a program called HydroFORM-3D developed here on the basis of a rigid–plastic model, has been applied to the lower arm hydroforming. The friction calculation between die and workpiece has been dealt with carefully by introducing a new scheme in three-dimensional surface integration. To accomplish successful hydroforming process design, thorough investigation on the proper combination of process parameters such as internal hydraulic pressure, axial feeding and tool geometry has been performed. Results obtained from numerical simulation for a lower arm in the hydroforming process are compared with a series of experiments. The comparison shows that the numerical analysis successfully provides the manufacturing information on the lower arm hydroforming, and it predicts the geometrical deformation and the thinning.

Manufacture of an automobile lower arm by hydroforming

The recent application of tube hydroforming in the automotive industry demands finite element analysis, since it is rapidly being used as an effective tool for the evaluation and optimisation of the design of hydroforming dies and processes. In this paper, attention is paid to the comparison of an implicit and an explicit FEM widely used for the hydroforming process. The influences of time scaling and mass scaling, which have been commonly used in order to save computational time in the explicit method, are especially investigated. The comparisons focus on the predictability of wrinkling and stress with various scaling factors in the explicit method. Through verifications with experimental results, a useful guideline in determining the scaling factors is proposed.

Sung-Jong Kang

Papers

A prediction of bursting failure in tube hydroforming processes based on ductile fracture criterion

Manufacture of an automobile lower arm by hydroforming

A comparative study of implicit and explicit FEM for the wrinkling prediction in the hydroforming process

Analysis and design of hydroforming processes by the rigid–plastic finite element method

Rigid–plastic finite element analysis of hydroforming process and its applications