Finite element modelling and control of new metal forming processes

doi:10.1016/j.ijmachtools.2006.01.031

International Journal of Machine Tools and Manufacture

Volume 46, Issue 11, September 2006, Pages 1194-1200

https://doi.org/10.1016/j.ijmachtools.2006.01.031 Get rights and content

Abstract

The classical formulations for material forming either in the solid or in the liquid state are briefly recalled, in terms of material constitutive behavior, friction law, integral forms and finite element discretization. A few important numerical issues are discussed, including meshing, remeshing and adaptivity, parallel computing and coupling between work-piece and tools. Five examples of applications of finite element models to new processes are presented: friction stir welding, hot stamping of quenchable steels, tube hydroforming, thixoforming and self piercing riveting. It is concluded that many new forming processes can be designed and optimized much more effectively using the numerical simulation technology.

Introduction

Finite element modeling of metal forming processes started in the seventies after the work of Cornfield [1], Kobayashi [2] and Zienkiewicz [3], for 2D flow mostly at the laboratory level. Then 2D and 3D computer codes appeared for the simulation of rolling, considered as a stationary process. In the 1980s, 2D and 3D computer codes for non steady-state processes were developed at the laboratory level and transferred to software companies for marketing. For example the beginning of the Forge3^® code was first acknowledged in 1986 by Surdon [4] and marketed in the 1990s. Today there are several 3D computer codes on the market, specialized mostly either for the simulation of forging or for deep-drawing processes, or for conventional casting.

In industry we observe a constant evolution of the manufacturing processes, in order to improve the quality of the work-pieces, or/and to reduce the cost or forming, the flexibility of the processes, etc. New processes appear regularly and their evaluation in specific contexts depends more and more crucially on the possibility of numerical simulation in order to assess the feasibility and to optimize the process, with severe constraints on the delays. The objective of this paper is to analyze the possibility to utilize existing codes to model in a realistic way new non-conventional forming processes.

Section snippets

Mechanical and numerical formulations

The objective of this section is to recall schematically the main scientific ingredients which must be mastered for developing a versatile finite element simulation code for metal forming analysis in industry. More details can also be found in [5].

Numerical issues

We shall review only a few numerical problems which have been recently considered in order to enhance the user friendliness of the codes. These improvements have been achieved in particular by introducing automatic meshing and adaptive refinement modules, decreasing the computational time by taking advantage of modern parallel computers and offering the possibility to extend the calculation to the tools domains.

Examples of simulation of new forming processes

A few examples are presented in order to show the possibilities of a forging code Forge3^®, or an injection code Rem3D^®, to be utilized, with minor adaptations, to treat new metal forming processes and help the engineer to design forming sequences and optimize them.

Conclusions

After a brief survey of the mechanical and mathematical basic formulations suitable for material forming, the key numerical issues were discussed. To demonstrate the interest of numerical modeling for design and optimization of the new forming processes, a few examples were analyzed. It appears that the main technological parameters can be predicted with existing models, or with reasonable updates of these computer codes.

In the future it is expected that the final microstructures and the

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A good agreement was found between experimental values and calculated results. In Chenot and Massoni’s paper [101], some important numerical issues were discussed, including meshing, remeshing and adaptivity, parallel computing and coupling between work-piece and tools. Five example applications of FE models to new processes were presented: the FSW, hot stamping of quenchable steels, tube hydroforming, thixoforming and self-piercing riveting.
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Finite element modelling and control of new metal forming processes

Abstract

Introduction

Section snippets

Mechanical and numerical formulations

Numerical issues

Examples of simulation of new forming processes

Conclusions

Computational Methods for Applied Mechanical Engineering

Theoretical prediction of plastic flow in hot rolling including the effect of various temperature distribution

Journal of Iron and Steel Institute

New solutions to rigid plastic deformation problems using a matrix method

Journal of Engineering for Industry

Flow of plastic and visco-plastic solids with special reference to extrusion and forming processes

International Journal for Numerical Methods in Engineering

Finite element calculations of three-dimensional hot forging

Metal Forming Analysis

Mesh topology for mesh generation problems—Application to three-dimensional remeshing