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Identification of viscoplastic material parameters from spherical indentation data: Part II. Experimental validation of the method

Published online by Cambridge University Press:  01 March 2006

D. Klötzer
Affiliation:
Bundesanstalt für Materialforschung und -prüfung, 12200 Berlin, Germany
Ch. Ullner*
Affiliation:
Bundesanstalt für Materialforschung und -prüfung, 12200 Berlin, Germany
E. Tyulyukovskiy
Affiliation:
Forschungszentrum Karlsruhe, Institut für Materialforschung II, 76021 Karlsruhe, Germany
N. Huber
Affiliation:
Forschungszentrum Karlsruhe, Institut für Materialforschung II, 76021 Karlsruhe, Germany
*
a) Address all correspondence to this author. e-mail: [email protected]
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Abstract

A neural network-based analysis method for the identification of a viscoplasticity model from spherical indentation data, developed in the first part of this work [J. Mater. Res.21, 664 (2006)], was applied for different metallic materials. Besides the comparison of typical parameters like Young’s modulus and yield stress with values from tensile experiments, the uncertainties in the identified material parameters representing modulus, hardening behavior, and viscosity were investigated in relation to different sources. Variations in the indentation position, tip radius, force application rate, and surface preparation were considered. The extensive experimental validation showed that the applied neural networks are very robust and show small variation coefficients, especially regarding the important parameters of Young’s modulus and yield stress. On the other hand, important requirements were quantified, which included a very good spherical indenter geometry and good surface preparation to obtain reliable results.

Type
Articles
Copyright
Copyright © Materials Research Society 2006

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References

REFERENCES

1.Huber, N., Tsakmakis, Ch.: An experimental device for depth-sensing indentation tests in mm-scale. J. Mater. Res. 13, 1650 (1998).CrossRefGoogle Scholar
2.Kucharski, S. and Mróz, Z.: Identification of hardening parameters of metals from spherical indentation tests. Trans. ASME, J. Eng. Mater. Technol. 123, 245 (2001).CrossRefGoogle Scholar
3.Nayebi, A., Abdi, R. El, Bartier, O., Mauvoisin, G.: New procedure to determine steel mechanical parameters from the spherical indentation technique. Mech. Mater. 34, 243 (2002).CrossRefGoogle Scholar
4.Huber, N., Tyulyukovskiy, E.: A new loading history for identification of viscoplastic properties by spherical indentation. J. Mater. Res. 19, 101 (2004).CrossRefGoogle Scholar
5.Kucharski, S. and Mróz, Z.: Identification of material parameters by means of compliance moduli in spherical indentation test. Mater. Sci. Eng. A, Struct. Mater. 379, 448 (2004).CrossRefGoogle Scholar
6.Tyulyukovskiy, E., Huber, N.: Identification of viscoplastic material parameters from spherical indentation data: Part I. Neutral networks. J. Mater. Res. 21, 664 (2006).CrossRefGoogle Scholar
7. ISO standard 14577: Metallic materials—Instrumented indentation test for hardness and materials parameter; October 2003, -part 1: Test method, -part 2: Verification and calibration of the testing machine, -part 3: Calibration of reference test pieces.Google Scholar
8.Field, J.S., Swain, M.V.: Determining the mechanical properties of small volumes of material from submicrometer spherical indentations. J. Mater. Res. 10, 101 (1995).CrossRefGoogle Scholar
9.Ahn, J-H., Kwon, D.: Derivation of plastic stress-strain relationship from ball indentations. J. Mater. Res. 16, 3170 (2001).CrossRefGoogle Scholar
10.Dao, M., Chollacoop, N., Van Vliet, K.J., Venkatesh, T.A., Suresh, S.: Computational modeling of the forward and reverse problems in instrumented sharp indentation. Acta Materialia. 49, 3899 (2001).CrossRefGoogle Scholar
11.Cheng, Y-T., Cheng, C-M.: Scaling, dimensional analysis, and indentation measurements dimensional analysis, and indentation measurements. Mater. Sci. Eng. R 44, 91 (2004).CrossRefGoogle Scholar
12.Huber, N., Tsakmakis, Ch.: Determination of constitutive properties from spherical indentation data using neural networks, Part II: Plasticity with nonlinear isotropic and kinematic hardening. J. Mech. Phys. Solids . 47, 1589 (1999).CrossRefGoogle Scholar
13.Huber, N., Tsakmakis, Ch.: A neural network tool for identifying the material parameters of a finite deformation viscoplasticity model with static recovery. Comp Methods Appl. Mech. Eng. 191, 353 (2001).CrossRefGoogle Scholar
14.Oliver, W.C., Pharr, G.M.: An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments. J. Mater. Res. 7, 1564 (1992).CrossRefGoogle Scholar
15.Tabor, D.: Hardness of Metals (Cambridge University Press Cambridge 1951).Google Scholar