Incremental sheet forming process modelling - limitation analysis

• Autorzy: Pohlak M. , Majak J. , Küttner R.
• Języki publikacji: EN

Abstrakty

EN

Purpose: of this paper is incremental sheet forming (ISF) process modelling. Main attention is paid to limitation analysis. Two kinds of risks are considered: material failure and tool failure. Aim of the current study is to minimize both risks i.e. provide limits for safe manufacturing. Design/methodology/approach: Experimental, numerical and theoretical investigation is performed. The test procedures are designed for determining FLD and forming force components in ISF process. The ISF process is modelled using FEM software LS-DYNA (fully integrated shell elements). In numerical analysis the plastic anisotropy is considered (Hill's second and Barlat's higher order yield criteria). Findings: The influence of plastic anisotropy on two formability characteristics - FLD and forming load components is studied. In both cases the effect of plastic anisotropy is found to be significant. It is shown that variation of the Lankford coefficient(s) in range 0.5 - 3.0 may cause changes on the formability characteristics over ten percent. Research limitations/implications: Limitations on forming angle, complications with considering elastic spring-back. Practical implications: The estimates on forming load components can be used for tooling selection in order to avoid tool failure. The FLD can be used in order to separate safe and unsafe forming areas in ISF process. Originality/value: An approximate theoretical model is proposed (based on Iseki's model). Incremental sheet forming strategies for determining forming limit diagram (FLD) are pointed out.

Słowa kluczowe

EN

limitation analysis; design; technological design; plastic forming; plastic anisotropy

PL

analiza stanów granicznych; projekt; projekt technologiczny; obróbka plastyczna; anizotropia plastyczna

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2007
• Tom: Vol. 22, nr 2
• Strony: 67--70
• Opis fizyczny: Bibliogr. 15. poz., fot., rys.

Twórcy

autor

Pohlak M.

autor

Majak J.

autor

Küttner R.

• Mechanics Department, Tallinn University of Technology, Ehitajate tee 5, Tallinn 19086 Estonia,

Bibliografia

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