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Constitutive modeling for strain rate-dependent behaviors of nanocrystalline materials based on dislocation density evolution and strain gradient

Published online by Cambridge University Press:  26 November 2014

Youyi Wu
Affiliation:
School of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, Jiangsu 210009, China
Jianqiu Zhou*
Affiliation:
School of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, Jiangsu 210009, China; and School of Mechanical & Electrical Engineering, Wuhan Institute of Technology, Wuhan, Hubei 430070, China
Shuhong Dong
Affiliation:
School of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, Jiangsu 210009, China
Aosheng Hu
Affiliation:
School of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, Jiangsu 210009, China
Lu Wang
Affiliation:
School of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, Jiangsu 210009, China
Xuming Pang
Affiliation:
School of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, Jiangsu 210009, China
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

To evaluate the influence of strain rate on mechanical behavior of nanocrystalline (NC) materials, a phase mixture constitutive model composed of ordered grain interior phase and plastically softer grain boundary dislocation pile up zone phase was built. Because of dissimilar properties and mismatch between the two phases, dislocation density evolution controlling mechanism based on statistically stored dislocations and geometrically necessary dislocations was analyzed and extended to NC regime to consider their disparate effects. Based on the composite model, a new stress–strain constitutive relation for strain rate-dependent behaviors was firstly established based on dislocation density evolution and strain gradient theory. The calculated data were then compared with corresponding experimental curves and strong strain rate-dependent behaviors were exhibited, which indicated that the predictions kept in good agreement with experiments. Further discussions were presented for calculations of strain rate sensitivity and activation volume for NC Ni through the proposed model.

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Articles
Copyright
Copyright © Materials Research Society 2014 

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References

REFERENCES

Meyers, M.A., Mishra, A., and Benson, D.J.: Mechanical properties of nanocrystalline materials. Prog. Mater. Sci. 51(4), 427 (2006).CrossRefGoogle Scholar
Kumar, K.S., Van Swygenhoven, H., and Suresh, S.: Mechanical behavior of nanocrystalline metals and alloys11The Golden Jubilee Issue—Selected topics in Materials Science and Engineering: Past, Present and Future, edited by S. Suresh. Acta Mater. 51(19), 5743 (2003).Google Scholar
Koch, C.C.: Structural nanocrystalline materials: An overview. J. Mater. Sci. 42(5), 1403 (2007).Google Scholar
Dao, M., Lu, L., Asaro, R., Dehosson, J., and Ma, E.: Toward a quantitative understanding of mechanical behavior of nanocrystalline metals. Acta Mater. 55(12), 4041 (2007).Google Scholar
Liu, Y., Zhou, J., and Ling, X.: Impact of grain size distribution on the multiscale mechanical behavior of nanocrystalline materials. Mater. Sci. Eng., A 527(7–8), 1719 (2010).CrossRefGoogle Scholar
Koch, C.C.: Ductility in nanostructured and ultra fine-grained materials: Recent evidence for optimism. J. Metastable Nanocryst. Mater. 18, 9 (2002).Google Scholar
Wang, Y.M., Wang, K., Pan, D., Lu, K., Hemker, K.J., and Ma, E.: Microsample tensile testing of nanocrystalline copper. Scr. Mater. 48(12), 1581 (2003).CrossRefGoogle Scholar
Weertman, J., Farkas, D., Hemker, K., Kung, H., Mayo, M., Mitra, R., and Swygenhoven, H.V.: Structure and mechanical behavior of bulk nanocrystalline materials. MRS Bull. 24(02), 44 (1999).Google Scholar
Schwaiger, R., Moser, B., Dao, M., Chollacoop, N., and Suresh, S.: Some critical experiments on the strain-rate sensitivity of nanocrystalline nickel. Acta Mater. 51(17), 5159 (2003).CrossRefGoogle Scholar
Cheng, S., Ma, E., Wang, Y., Kecskes, L., Youssef, K., Koch, C., Trociewitz, U., and Han, K.: Tensile properties of in situ consolidated nanocrystalline Cu. Acta Mater. 53(5), 1521 (2005).CrossRefGoogle Scholar
Fleck, N.A., Muller, G.M., Ashby, M.F., and Hutchinson, J.W.: Strain gradient plasticity: Theory and experiment. Acta Metall. Mater. 42(2), 475 (1994).Google Scholar
Stölken, J. and Evans, A.: A microbend test method for measuring the plasticity length scale. Acta Mater. 46(14), 5109 (1998).Google Scholar
Nix, W.D. and Gao, H.: Indentation size effects in crystalline materials: A law for strain gradient plasticity. J. Mech. Phys. Solids 46(3), 411 (1998).Google Scholar
Saha, R., Xue, Z., Huang, Y., and Nix, W.D.: Indentation of a soft metal film on a hard substrate: Strain gradient hardening effects. J. Mech. Phys. Solids 49(9), 1997 (2001).Google Scholar
Smyshlyaev, V. and Fleck, N.: The role of strain gradients in the grain size effect for polycrystals. J. Mech. Phys. Solids 44(4), 465 (1996).CrossRefGoogle Scholar
Ma, L., Zhou, J., Zhu, R., and Li, S.: Effects of strain gradient on the mechanical behaviors of nanocrystalline materials. Mater. Sci. Eng., A 507(1–2), 42 (2009).Google Scholar
Hall, E.: The deformation and ageing of mild steel: III discussion of results. Proc. Phys. Soc., London, Sect. B 64(9), 747 (1951).Google Scholar
Petch, N.J.: The cleavage strength of polycrystals. J. Iron Steel Inst. 174, 25 (1953).Google Scholar
Li, J.C.: Petch relation and grain boundary sources. Trans. Metall. Soc. AIME 227(1), 239 (1963).Google Scholar
Ashby, M.F.: The deformation of plastically non-homogeneous materials. Philos. Mag. 21(170), 399 (1970).Google Scholar
Fougere, G., Weertman, J., Siegel, R., and Kim, S.: Grain-size dependent hardening and softening of nanocrystalline Cu and Pd. Scr. Metall. Mater. 26(12), 1879 (1992).CrossRefGoogle Scholar
Schuh, C., Nieh, T., and Yamasaki, T.: Hall–Petch breakdown manifested in abrasive wear resistance of nanocrystalline nickel. Scr. Mater. 46(10), 735 (2002).Google Scholar
Kumar, K.S., Suresh, S., Chisholm, M.F., Horton, J.A., and Wang, P.: Deformation of electrodeposited nanocrystalline nickel. Acta Mater. 51(2), 387 (2003).Google Scholar
Derlet, P. and Van Swygenhoven, H.: Length scale effects in the simulation of deformation properties of nanocrystalline metals. Scr. Mater. 47(11), 719 (2002).Google Scholar
Yamakov, V., Wolf, D., Phillpot, S.R., Mukherjee, A.K., and Gleiter, H.: Dislocation processes in the deformation of nanocrystalline aluminium by molecular-dynamics simulation. Nat. Mater. 1(1), 45 (2002).Google Scholar
Hung, P., Sun, P., Yu, C., Kao, P., and Chang, C.: Inhomogeneous tensile deformation in ultrafine-grained aluminum. Scr. Mater. 53(6), 647 (2005).CrossRefGoogle Scholar
Capolungo, L., Jochum, C., Cherkaoui, M., and Qu, J.: Homogenization method for strength and inelastic behavior of nanocrystalline materials. Int. J. Plast. 21(1), 67 (2005).Google Scholar
Follansbee, P.S. and Kocks, U.F.: A constitutive description of the deformation of copper based on the use of the mechanical threshold stress as an internal state variable. Acta Metall. 36(1), 81 (1988).Google Scholar
Jia, D., Ramesh, K.T., and Ma, E.: Effects of nanocrystalline and ultrafine grain sizes on constitutive behavior and shear bands in iron. Acta Mater. 51(12), 3495 (2003).CrossRefGoogle Scholar
Kim, H.S., Estrin, Y., and Bush, M.B.: Constitutive modelling of strength and plasticity of nanocrystalline metallic materials. Mater. Sci. Eng., A 316(1), 195 (2001).CrossRefGoogle Scholar
Shu, J.Y. and Fleck, N.A.: Strain gradient crystal plasticity: Size-dependent deformation of bicrystals. J. Mech. Phys. Solids 47(2), 297 (1999).Google Scholar
Yamakov, V., Wolf, D., Phillpot, S., and Gleiter, H.: Grain-boundary diffusion creep in nanocrystalline palladium by molecular-dynamics simulation. Acta Mater. 50(1), 61 (2002).Google Scholar
Zhu, L. and Lu, J.: Modelling the plastic deformation of nanostructured metals with bimodal grain size distribution. Int. J. Plast. 3031, 166 (2012).Google Scholar
Zhou, J., Li, Z., Zhu, R., Li, Y., and Zhang, Z.: A mixtures-based model for the grain size dependent mechanical behavior of nanocrystalline materials. J. Mater. Process. Technol. 197(1–3), 325 (2008).Google Scholar
Zhou, J., Zhu, R., and Zhang, Z.: A constitutive model for the mechanical behaviors of bcc and fcc nanocrystalline metals over a wide strain rate range. Mater. Sci. Eng., A 480(1–2), 419 (2008).Google Scholar
Gao, C.Y. and Zhang, L.C.: Constitutive modelling of plasticity of fcc metals under extremely high strain rates. Int. J. Plast. 3233, 121 (2012).Google Scholar
Gao, H., Huang, Y., Nix, W., and Hutchinson, J.: Mechanism-based strain gradient plasticity—I. Theory. J. Mech. Phys. Solids 47(6), 1239 (1999).CrossRefGoogle Scholar
Kocks, U. and Mecking, H.: Physics and phenomenology of strain hardening: The FCC case. Prog. Mater. Sci. 48(3), 171 (2003).Google Scholar
Wu, X., Zhu, Y., Wei, Y., and Wei, Q.: Strong strain hardening in nanocrystalline nickel. Phys. Rev. Lett. 103(20), 205504 (2009).CrossRefGoogle ScholarPubMed
Dalla Torre, F., Van Swygenhoven, H., and Victoria, M.: Nanocrystalline electrodeposited Ni: Microstructure and tensile properties. Acta Mater. 50(15), 3957 (2002).Google Scholar
Wang, L., Zhou, J., Zhang, S., Liu, H., and Dong, S.: Effect of dislocation–GB interactions on crack blunting in nanocrystalline materials. Mater. Sci. Eng., A 592, 128 (2014).Google Scholar
Zhu, R.T., Zhang, X.X., Li, Y.F., and Zhou, J.Q.: Impact behavior and constitutive model of nanocrystalline Ni under high strain rate loading. Mater. Des. 49, 426 (2013).Google Scholar
Gu, C.D., Lian, J.S., Jiang, Q., and Zheng, W.T.: Experimental and modelling investigations on strain rate sensitivity of an electrodeposited 20 nm grain sized Ni. J. Phys. D: Appl. Phys. 40(23), 7440 (2007).Google Scholar
Wang, Y.M. and Ma, E.: On the origin of ultrahigh cryogenic strength of nanocrystalline metals. Appl. Phys. Lett. 85(14), 2750 (2004).Google Scholar