Damage in sheet metal forming: prediction of necking phenomenon
Keywords:
plastic instability, yield locus, damage mode/, prediction, FE simulationAbstract
Necking is a phenomenon limiting sheet metal-forming processes. The linearised perturbation technique is presented and adapted to various cases of yield criteria, damage models and 2D/3D stress states. Sorne aspects about calculations are given. Final/y two applications of these works are shawn. The first one validates the theory by establishing Forming Limit Diagrams. The second one is the implementation in a FE code and presents the necking predictions obtained on industrial cases ofmetal-forming.
Downloads
References
[ARR 89] ARRIEUX R., Boivin M., "Theoretical determination of the forming limit stress
curve for isotropie sheet materials", Annals of the C!RP, 38/1, 1989, p. 261-264.
(BAN 99] BANABIC D., BALAN T., POHLANDT K., "Analytical and experimental investigation
on anisotropie yield criteria", 6'h /nt. Conf /CTP'99, Nuremberg, 1999, p. 1411-1416.
[BAN 00] BANABIC D., COMSA D.S., BALAN T., "A new yield criterion for orthotropic sheet
metals under plane-stress conditions", Proc. of TPR 2000, International section, ClujNapoca,
-12 May, 2000, p. 217-224.
[BAR 91] BARLAT F., LEGE D.J., BREM J.C., "A six-component yield function for anisotropie
materials", /nt. 1. ofPlasticity, Vol. 7,1991, p. 693-712.
[BAS 77] BASSANI J.L., "Yield characterisation of metals with transversally isotropie plastic
properties", /nt. 1. Mech. Sei., Vol. 19, 1977, p. 651-654.
[BOU 94] BOUDEAU N., GELIN J.C., "Prediction of the Iocalized necking in 3D sheet metal
forming processes from FE simulations", J. of Mat. Process. Tech., V. 45, 1994, p. 229-235.
[BOU 00] BouoEAU N., GELIN J.C., "Necking in sheet metal forming. Influence of
macroscopic and microscopie properties ofrnaterials", /nt. J. Mech. Sei., Vol. 42, 2000, p.
-2232.
[BRU 95] BRUNET M., ARRtEUX R., NGUYEN NHAT T., "Necking prediction using forming
limit stress surfaces in 3D sheet metal forming simulation", Proc. of Numiform '95, 1995.
(BRU 97] BRUNET M., MGUIL-TOUCHAL S;, MORESTIN F., "Numerical and experimental
analysis of necking in 3D sheet metal forming processes using damage variable", in
Advanced Methods in Materials Processing Defects, edited by M. Predeleanu and P.
Gilormini, 1997, p. 205-215.
[FRO 98] FROMENTIN S., Etablissement d'un critère de striction intrinsèque des tôles et
validation numérique par simulations d'emboutissage, Ph.D. thesis, University of Metz,
France, 1998.
[GEL 92] GELIN J.C., PREDELEANU M., "Recent advances in damage mechanics: modelling
and computational aspects", Fourth International Conference on Numerical Methods in
lndustrial Forming Processes, edited by Chenot J.L. et al., 1992, p. 89-98.
[GOO 68] GooowiN G.M., "Application of the strain analysis to steel metal forming in press
shop", La Metallurgia /tatiana, no 8, 1968, p. 767-772.
[GOT 77] GoTOH M., "A theory of plastic anisotropy based on a yield function of fourth
order", !nt. J. Mech. Sei., Vol. 19, 1977, p. 505-520.
[HIL 48] HILL R., "A theory of the yielding and plastic flow of anisotropie metals", Proc.
Roy. Soc., London, A 193, 1948, p. 281-297.
[HIL 52] HILL R., "On discontinuous plastic states, with special references to Iocalized
necking in thin sheets", J. Mech. Phys. Solids, Vol. 1, 1952, p. 19-30.
[HIL 79] HILL R., "Theoretical plasticity of textured aggregates", Math. Proc. Cambridge
Philosophical Soc., Vol. 85, 1979, p. 179-191.
[HIL 93] HILL R., "A User-friendly theory of orthotropic plasticity in sheet metals", /nt. J.
Mech. Sei., Vol. 15, 1993, p. 19-25.
[HOR 96] HORA P., TONG L., REISSNER J., "Prediction method for ductile sheet metals failure
in FE simulation", Third /nt. Conf ln Numerical Simulation of 3D Sheet Metal Forming
Processes, edited by J.K. Lee et al., 1996, p. 252-256.
[HOS 79] HosFORD W.F., "On Yield loci of anisotropie cubic metals", Proc. 7'h North
American Metalworking Conf, SME, Dearbom, MI, 1979, p. 191-197.
[ITO OO]ITo K., SATOH K., GOYA M., YOSHIDA T., "Prediction of limit strain in sheet metalforming
processes by 3D analysis of localized necking", !nt. J. Mech. Sei., Vol 42, n° 11,
,p. 2233-2248.
[KAR 93] KARAFII..l..IS A.P., BoYCE M.C., "A general anisotropie yield criterion using bounds
and a tranformation weighting tensor ", J. Mech. Phys. Solids, Vol. 41, 1993, p. 1859-1886.
[KEE 65] KEELER S.P., "Determination of the forming limits in automotive stamping", Sheet
metal industries, Vol 42, no 461, 1965, p. 683-691.
[KNO 00] KNOCKAERT R., MASSON! E., CHASTEL Y., "Prediction of strain localization during
sheet forming operations", Third ESAFORM Conference on Material Forming, Stuttgart,
Deutschland, 2000, Il, p. 7-10.
[LES 00] LESTRIEZ P., Prédiction de striction localisée par l'analyse linéarisée de stabilité:
application au critère de plasticité de BANABIC, Rapport de DEA, Université de
Franche-Comté - ENSMM, France, Septembre 2000.
[MOL 85] MOLINARI A., "Instabilité thermoviscoplastique en cisaillement simple", Journal
de Mécanique Théorique et Appliquée, Vol 4, no 5, 1985, p. 659-684.
