A simple algorithm for formability analysis

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

Abstrakty

EN

Purpose: of this paper is to develop a simple algorithm for local and diffuse necking analysis, which covers different yield criteria and strain hardening laws. Design/methodology/approach: Theoretical study, application of plasticity theory. Numerical analysis, FLD determination. Experimental verification (material parameters and FLD). Comparison of obtained results with the results available in literature. Both, stress and strain based FLD-s are considered. Findings: The dimensionless in stability tensors are introduced. The plastic instability criterion in tensor notation is derived. The capabilities of the derived instability criteria are improved using different anisotropic yield criteria from Hill48 up to BBC2003. A test procedure for determining material properties and forming limits in plane strain condition for sheet metal is performed. Reseach limitations/implications: The study is based on classical instability conditions. The stress-strain behavior of the material is described with empirical equation (the strain rate and also temperature dependence of the flow stress are not considered). Practical implications: The forming limit curve determined defines boundary between elastic or stable plastic deformation (below curve) and unsafe flow (above curve). The risk of failure is determined by the distance between the actual strain condition in the forming process and the forming limit curve. Originality/value: A simple algorithm for local and diffuse necking analysis is proposed. The dimensionless instability tensors introduced can be used for theoretical improvements.

Słowa kluczowe

EN

numerical techniques; formability; plastic anisotropy

PL

techniki numeryczne; odkształcalność; anizotropia plastyczna

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2007
• Tom: Vol. 22, nr 1
• Strony: 57--60
• Opis fizyczny: Bibliogr. 20 poz., rys.

Twórcy

autor

Majak J.

autor

Pohlak M.

autor

Küttner R.

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

Bibliografia

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