[en] Inverse methods offer a powerful tool for the determination of the elasto-plastic material properties. Contrary to standard tests, these methods can deal with heterogeneous stress and strain-fields which have a larger information contents and hence allow the simultaneous identification of several material parameters. Moreover, it is expected that the obtained material parameters are more accurate, since these heterogeneous deformation fields are much closer to those occurring in real (metal) forming operations. The principle of the inverse method for the identification of material parameters presented in this paper is to compare an experimentally measured strain field to that computed by a Finite Element (FE) model. The material parameters in the FE model are iteratively tuned in such a way that both strain fields match each other as closely as possible. One of the building blocks in this identification procedure is the updating algorithm for the material parameters in the FE model. The key problem of this updating algorithm is the determination of the sensitivity matrix, which expresses the sensitivities of the strains with respect to the material parameters. This paper presents an analytical method for the calculation of this sensitivity matrix in case of simple tensile tests.
Disciplines :
Materials science & engineering
Author, co-author :
Cooreman, Steven
Bouffioux, Chantal ; Université de Liège - ULiège > Département Argenco : Secteur MS2F > Département Argenco : Secteur MS2F
Lecompte, David
Sol, Hugo
Vantomme, John
Debruyne, Dimitri
Language :
English
Title :
Computation of the sensitivity matrix used for Elasto-plastic material parameter identification by inverse methods
Publication date :
2006
Event name :
7th national congress on theoretical and applied Mechanics
Event place :
Mons, Belgium
Event date :
May 2006
Audience :
International
Main work title :
Congress on theoretical and applied Mechanics, Mons, Belgium, May 2006
Bridgman, P.W., (1952) Studies in Large Plastic Flow and Fracture, , McGraw Hill, New York
Chen, D.J., Chiang, F.P., Tan, Y.S., Don, H.S., Digital speckle displacement measurement using a complex Fourier spectrum method (1993) Applied Optics, 32 (11), pp. 1839-1849
Ghouati, O., Gelin, J.C., An inverse approach for the identification of complex material behaviours (1997) Material Identification using Mixed Numerical Experimental Methods, pp. 93-102. , Sol H., and Oomens C.W.J. (Eds), Kluwer Academic Publishers, Dordrecht
Ghouati, O., Gelin, J.-C., Identification of material parameters directly from metal forming processes (1998) Journal of Materials Processing Technology, pp. 560-564
Ghouati, O., Gelin, J.-C., A finite element-based identification method for complex metallic material behaviour (2001) Computational Materials Science, 21, pp. 57-68
Grédiac, M., Pierron, F., Applying the Virtual Fields Method to the identification of elasto-plastic constitutive parameters (2006) International Journal of Plasticity, 22, pp. 602-627
Kajberg, J., Lindkvist, G., Characterization of materials subjected to large strains by inverse modelling based on in-plane displacement fields (2004) International Journal of Solids and Structures, 42, pp. 3439-3459
Koc, P., Štok, B., Computer-aided identification of the yield curve of a sheet metal after onset of necking (2004) Computational Materials Science, 31, pp. 155-168
Ling, Y., Uniaxial true stress-strain after necking (1996) AMP Journal of Technology, 5, pp. 37-48
Meuwissen, M., Oomens, C., Baaijens, F., Petterson, R., Janssen, J., Determination of parameters in elasto-plastic models of aluminium (1997) Material Identification using Mixed Numerical Experimental Methods, pp. 71-80. , Sol H., and Oomens C.W.J. (Eds), Kluwer Academic Publishers, Dordrecht
Meuwissen, M., Oomens, C., Baaijens, F., Petterson, R., Janssen, J., Determination of the elasto-plastic properties of aluminium using a mixed numerical-experimental procedure (1998) Journal of Materials Processing Technology, 75, pp. 204-211
Shi, Y., Sol, H., Hua, H., Transverse shear modulus identification by an inverse method using measured flexural resonance frequencies from beams (2005) Journal of Sound and Vibrations, 285 (1-2), pp. 425-442
Sol, H., Hua, H., De Visscher, J., Vantomme, J., De Wilde, W.P., A mixed numerical/experimental technique for the nondestructive identification of the stiffness properties of fibre reinforced composite materials (1997) Journal of NDT&E International, 30 (2), pp. 88-91
Synnergren, P., Sjoedahl, M., A stereoscopic digital speckle photography system for 3-d displacement field measurements (1999) Optics and Lasers in Engineering, 31, pp. 425-433
