A unified model for obtaining stress-strain relationship under spherical indenter loading and test application

  • Haomin WANG ,
  • Lixun CAI ,
  • Huairong XIAO
Expand
  • Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province, School of Mechanics and Aerospace Engineering, Southwest Jiaotong University, Chengdu 610031, China
Lixun CAI, E-mail: lix_cai@263.net

Received date: 2025-01-06

  Revised date: 2025-05-27

  Online published: 2025-07-28

Supported by

Project supported by the National Natural Science Foundation of China (Nos. 11872320 and 12072294)

Copyright

© Shanghai University 2025

Abstract

A dimensionless load-displacement model based on the energy-density equivalence principle is proposed to obtain the stress-strain relationships of metallic materials under monotonic indentations with various diameters of spherical indenters. Finite element simulations are carried out to verify the constitutive relations from the new model, involving indentations made with various spherical indenters. For each indenter, some quasi-static spherical indentation tests are conducted on the materials with 40 preset constitutive relationships. The results indicate that the stress-strain curves predicted by the model align with the preset curves under 200 loading conditions. Moreover, the goodness-of-fit between the predicted stress-strain curves and the preset curves exceeds 0.96 for all indenters and materials. In the end, the indentation tests are conducted by the spherical indenters with the diameters of 1.587 mm for fifteen metallic materials and 1 mm for eight metallic materials. The results show that the stress-strain curves obtained by the spherical indentation based on the new model closely match those obtained from the uniaxial tensile tests. The relative errors for both the proof strength at 0.2% plastic extension and the tensile strength are below 5%.

Cite this article

Haomin WANG , Lixun CAI , Huairong XIAO . A unified model for obtaining stress-strain relationship under spherical indenter loading and test application[J]. Applied Mathematics and Mechanics, 2025 , 46(8) : 1591 -1608 . DOI: 10.1007/s10483-025-3283-6

References

[1] BRINELL, J. A. Way of determining the hardness of bodies and some applications of the same. Teknisk Tidskrift, 5, 69 (1900)
[2] DOERNER, M. F. and NIX, W. D. A method for interpreting the data from depth-sensing indentation instruments. Journal of Materials Research, 1(4), 601–609 (1986)
[3] OLIVER, W. C. and PHARR, G. M. An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments. Journal of Materials Research, 7(6), 1564–1583 (1992)
[4] ZHANG, Z. J., CAI, L. X., CHEN, H., BAO, C., and LIU, X. K. Spherical indentation method to determine stress-strain relations and tensile strength of metallic materials (in Chinese). Chinese Journal of Theoretical and Applied Mechanics, 51(1), 159–169 (2019)
[5] TABOR, D. The Hardness of Metals, Oxford University Press, Oxford (2000)
[6] CHENG, Y. T. and CHENG, C. M. Scaling relationships in conical indentation of elastic-perfectly plastic solids. International Journal of Solids and Structures, 36(8), 1231–1243 (1999)
[7] HAGGAG, F. M. In-situ measurements of mechanical properties using novel automated ball indentation system. Small Specimen Test Techniques Applied to Nuclear Reactor Vessel Thermal Annealing and Plant Life Extension, ASTM STP 1204, American Society for Testing and Materials, Philadelphia (1993)
[8] AHN, J. and KWON, D. Derivation of plastic stress-strain relationship from ball indentations: examination of strain definition and pileup effect. Journal of Materials Research, 16(11), 3170–3178 (2001)
[9] SI, S. Q., CAI, L. X., CHEN, H., BAO, C., and LIU, X. K. Theoretical model and testing method for ball indentation based on the proportional superposition of energy in pure elasticity and pure plasticity. Chinese Journal of Aeronautics, 35(2), 141–153 (2022)
[10] WU, S. B., XU, T., YU, C., and LU, Y. Y. Measurement of tensile properties of 16MnR steel by ball indentation method (in Chinese). Materials for Mechanical Engineering, 39(1), 82–85 (2015)
[11] CHEN, H., CAI, L. X., and BAO, C. Equivalent-energy indentation method to predict the tensile properties of light alloys. Materials & Design, 162, 322–330 (2019)
[12] HILL, R., STORAKERS, B., and ZDUNEK, A. B. A theoretical study of the Brinell hardness test. Proceedings of the Royal Society of London, Serials A: Mathematical and Physical Sciences, 423(1865), 301–330 (1989)
[13] JOHNSON, K. L. The correlation of indentation experiments. Journal of the Mechanics and Physics of Solids, 18(2), 115–126 (1970)
[14] ZHANG, T., JIANG, P., FENG, Y., and YANG, R. Numerical verification for instrumented spherical indentation techniques in determining the plastic properties of materials. Journal of Materials Research, 24, 3653–3663 (2009)
[15] JIANG, P., ZHANG, T., FENG, Y., YANG, R., and LIANG, N. Determination of plastic properties by instrumented spherical indentation: expanding cavity model and similarity solution approach. Journal of Materials Research, 24(3), 1045–1053 (2009)
[16] ATTAF, M. T. Connection between the loading curve models in elastoplastic indentation. Materials Letters, 58(27-28), 3491–3498 (2004)
[17] JIANG, P., ZHANG, T. H., YANG, R., and LIANG, N. G. Extraction of plastic mechanical parameters of materials based on spherical compression method (in Chinese). Chinese Journal of Theoretical and Applied Mechanics, 41(5), 730–738 (2009)
[18] HUBER, N. and TSAKMAKIS, C. Determination of constitutive properties from spherical indentation data using neural networks, part i: the case of pure kinematic hardening in plasticity laws. Journal of the Mechanics and Physics of Solids, 47(7), 1569–1588 (1999)
[19] TYULYUKOVSKIY, E. and HUBER, N. Identification of viscoplastic material parameters from spherical indentation data, part I: neural networks. Journal of Materials Research, 21(3), 664–676 (2006)
[20] ZHANG, C., LOU, Y., and ZHANG, S. Large strain flow curve identification for sheet metals under complex stress states. Mechanics of Materials, 161, 103997 (2021)
[21] YAO, D., CAI, L., and BAO, C. A new fracture criterion for ductile materials based on a finite element aided testing method. Materials Science and Engineering: A, 673, 633–647 (2016)
[22] CHEN, H. and CAI, L. X. Theoretical model for predicting uniaxial stress-strain relation by dual conical indentation based on equivalent energy principle. Acta Materialia, 121, 181–189 (2016)
[23] CHEN, H. and CAI, L. X. Unified elastoplastic model based on strain energy equivalence principle. Applied Mathematical Modelling, 52, 664–671 (2017)
[24] CHEN, H. and CAI, L. X. An elastoplastic energy model for predicting the deformation behaviors of various structural components. Applied Mathematical Modelling, 68, 405–421 (2019)
[25] GB/T 37782-2019. Determination of Strength, Hardness and Stress-Strain Curves for Metallic Materials by Indentation Test (in Chinese), State Administration for Market Regulation and Standardization of China (2019)
[26] CHEN, H., CAI, L., and BAO, C. Equivalent-energy indentation method to predict the tensile properties of light alloys. Materials & Design, 162, 322–330 (2019)
[27] HOLLOMON, J. H. Tensile deformation. Metals Technology, 12, 268–290 (1945)
[28] HUANG, M., CAI, L., and HAN, G. Semi-analytical expressions to describe stress fields near the tip of Mode-I crack under plane-strain conditions. Applied Mathematical Modelling, 108, 724–747 (2022)
[29] HAN, G., CAI, L., XIAO, H., and HUANG, M. A novel flat indentation test method for obtaining stress-strain relationships of metallic materials based on energy density equivalence. International Journal of Solids and Structures, 269, 112–195 (2023)
[30] CHEN, H. Median Energy Equivalent Theory and Small Sample Material Test Method (in Chinese), Ph. D. dissertation, Southwest Jiaotong University, 32–33 (2019)
[31] ZHANG, S. Q. Discussion on goodness-of-fit indices for curved regression (in Chinese). Chinese Journal of Health Statistics, 19(1), 9–11 (2002)
Outlines

/

APS Journals | CSTAM Journals | AMS Journals | EMS Journals | ASME Journals