Skip to main content
Log in

Role of free volume in strain softening of as-cast and annealed bulk metallic glass

  • Article
  • Published:
Journal of Materials Research Aims and scope Submit manuscript

Abstract

Plasticity in amorphous alloys is associated with strain softening, induced by the creation of additional free volume during deformation. In this paper, the role of free volume, which was a priori in the material, on work softening was investigated. For this, an as-cast Zr-based bulk metallic glass (BMG) was systematically annealed below its glass transition temperature, so as to reduce the free volume content. The bonded-interface indentation technique is used to generate extensively deformed and well defined plastic zones. Nanoindentation was utilized to estimate the hardness of the deformed as well as undeformed regions. The results show that the structural relaxation annealing enhances the hardness and that both the subsurface shear band number density and the plastic zone size decrease with annealing time. The serrations in the nanoindentation load-displacement curves become smoother with structural relaxation. Regardless of the annealing condition, the nanohardness of the deformed regions is ∼12–15% lower, implying that the prior free volume only changes the yield stress (or hardness) but not the relative flow stress (or the extent of strain softening). Statistical distributions of the nanohardness obtained from deformed and undeformed regions have no overlap, suggesting that shear band number density has no influence on the plastic characteristics of the deformed region.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. C.A. Schuh, T.C. Hufnagel, and U. Ramamurty: Mechanical behavior of amorphous alloys. Acta Mater. 55, 4067 (2007).

    Article  CAS  Google Scholar 

  2. K.E. Prasad, R. Raghavan, and U. Ramamurty: Temperature dependence of pressure sensitivity in a metallic glass. Scr. Mater. 57, 121 (2007).

    Article  CAS  Google Scholar 

  3. M.N.M. Patnaik, R. Narasimhan, and U. Ramamurty: Spherical indentation response of metallic glasses. Acta Mater. 52, 3335 (2007).

    Article  CAS  Google Scholar 

  4. P. Tandaiya, R. Narasimhan, and U. Ramamurty: Mode I crack tip fields in amorphous materials with application to metallic glasses. Acta Mater. 55, 6541 (2007).

    Article  CAS  Google Scholar 

  5. F. Spaepen: A microscopic mechanism for steady state inhomogeneous flow in metallic glasses. Acta Metall. 25, 407 (1977).

    Article  CAS  Google Scholar 

  6. A.S. Argon: Plastic deformation in metallic glasses. Acta Metall. 27, 47 (1979).

    Article  CAS  Google Scholar 

  7. C.T. Liu, L. Heatherly, D.S. Easton, C.A. Carmichael, J.H. Schneibel, C.H. Chen, J.L. Wright, M.H. Yoo, J.A. Horton, and A. Inoue: Test environments and mechanical properties of Zr-base bulk amorphous alloys. Metall. Mater. Trans. A 29, 1811 (1998).

    Article  Google Scholar 

  8. M. Lind, G. Duan, and W.L. Johnson: Isoconfigurational elastic constants and liquid fragility of a bulk metallic glass forming alloy. Phys. Rev. Lett. 97, 015501 (2006).

    Article  CAS  Google Scholar 

  9. T. Egami: Formation and deformation of metallic glasses: Atom-istic theory. Intermetallics 14, 882 (2006).

    Article  CAS  Google Scholar 

  10. K-W. Park, J-I. Jang, M. Wakeda, Y. Shibutani, and J-C. Lee: Atomic packing density and its influence on the properties of Cu-Zr amorphous alloys. Scr. Mater. 57, 805 (2007).

    Article  CAS  Google Scholar 

  11. C. Nagel, K. Ratzke, E. Schmidtke, J. Wolfe, U. Geyer, and F. Faupel: Free-volume changes in the bulk metallic glass Zr46.7Ti8.3Cu7.5Ni10Be27.5 and the undercooled liquid. Phys. Rev. B 57, 10224 (1998).

    Article  CAS  Google Scholar 

  12. P. Tuinstra, P.A. Duine, J. Sietsma, and A. Vandenbeukel: The calorimetric glass-transition of amorphous Pd40Ni40P20. Acta Metall. Mater. 43, 2815 (1995).

    Article  CAS  Google Scholar 

  13. O.P. Bobrov, V.A. Khonik, S.N. Laptev, and M.Y. Yazvitsky: Comparative internal friction study of bulk and ribbon glassy Zr52.5Ti5Cu17.9Ni14.6Al10. Scr. Mater. 49, 255 (2003).

    Article  CAS  Google Scholar 

  14. A. Slipenyuk and J. Eckert: Correlation between enthalpy change and free volume reduction during structural relaxation of Zr55Cu30Al10Ni5 metallic glass. Scr. Mater. 50, 39 (2004).

    Article  CAS  Google Scholar 

  15. W. Dmowski, C. Fan, M.L. Morrison, P.K. Liaw, and T. Egami: Structural changes in bulk metallic glass after annealing below the glass-transition temperature. Mater. Sci. Eng., A 471, 125 (2007).

    Article  CAS  Google Scholar 

  16. U. Ramamurty, M.L. Lee, J. Basu, and Y. Li: Embrittlement of a bulk metallic glass due to low-temperature annealing. Scr. Mater. 47, 107 (2002).

    Article  CAS  Google Scholar 

  17. P. Murali and U. Ramamurty: Embrittlement of a bulk metallic glass due to sub-Tg annealing. Acta Mater. 53, 1467 (2005).

    Article  CAS  Google Scholar 

  18. R. Raghavan, P. Murali, and U. Ramamurty: Ductile to brittle transition in the Zr41.2Ti13.75Cu12.5Ni10Be22.5 bulk metallic glass. Intermetallics 14, 1051 (2006).

    Article  CAS  Google Scholar 

  19. H.W. Jin, R. Ayer, J.Y. Koo, R. Raghavan, and U. Ramamurty: Reciprocating wear mechanisms in a Zr-based bulk metallic glass. J. Mater. Res. 22, 264 (2007).

    Article  CAS  Google Scholar 

  20. M.E. Launey, R. Busch, and J.J. Kruzic: Effects of free volume changes and residual stresses on the fatigue and fracture behavior of a Zr-Ti-Ni-Cu-Be bulk metallic glass. Acta Mater. 56, 500 (2008).

    Article  CAS  Google Scholar 

  21. W.H. Jiang, F.E. Pinkerton, and M. Atzmon: Mechanical behavior of shear bands and the effect of their relaxation in a rolled amorphous Al-based alloy. Acta Mater. 53, 3469 (2005).

    Article  CAS  Google Scholar 

  22. W.H. Wang, C. Dong, and C.H. Shek: Bulk metallic glasses. Mater. Sci. Eng., R 44, 45 (2004).

    Article  CAS  Google Scholar 

  23. A.R. Yavari, J.J. Lewandowski, and J. Eckert: Mechanical properties of bulk metallic glasses. MRS Bull. 32, 635 (2007).

    Article  CAS  Google Scholar 

  24. C.A. Schuh and T.G. Nieh: A survey of instrumented indentation studies on metallic glasses. J. Mater. Res. 19, 46 (2004).

    Article  CAS  Google Scholar 

  25. R. Bhowmick, R. Raghavan, K. Chattopadhyay, and U. Ramamurty: Plastic flow softening in a bulk metallic glass. Acta Mater. 54, 4221 (2006).

    Article  CAS  Google Scholar 

  26. U. Ramamurty, S. Jana, Y. Kawamura, and K. Chattopadhyay: Hardness and plastic deformation in a bulk metallic glass. Acta Mater. 53, 705 (2005).

    Article  CAS  Google Scholar 

  27. W.C. Oliver and G.M. Pharr: An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments. J. Mater. Res. 7, 1564 (1992).

    Article  CAS  Google Scholar 

  28. W.C. Oliver and G.M. Pharr: Measurement of hardness and elastic modulus by instrumented indentation: Advances in understanding and refinements to methodology. J. Mater. Res. 19, 3 (2004).

    Article  CAS  Google Scholar 

  29. D. Suh and R.H. Dauskardt: Flow and fracture in Zr-based bulk metallic glasses. Ann. Chim.–Sci. Mat. 27, 25 (2002).

    Article  CAS  Google Scholar 

  30. R. Bohmer, K.L. Ngai, C.A. Angell, and D.J. Plazek: Nonexperimential relaxations in strong and fragile glass formers. J. Chem. Phys. 99, 4201 (1993).

    Article  Google Scholar 

  31. R. Raghavan, P. Murali, and U. Ramamurty: Influence of cooling rate on the enthalpy relaxation and fragility of a metallic glass. Metall. Mater. Trans. A 39, 1573 (2008).

    Article  CAS  Google Scholar 

  32. K.L. Johnson: Contact Mechanics, 1st ed. (Cambridge University Press, Cambridge, UK, 1985).

    Book  Google Scholar 

  33. C.A. Schuh and T.G. Nieh: A nanoindentation study of serrated flow in bulk metallic glasses. Acta Mater. 51, 87 (2003).

    Article  CAS  Google Scholar 

  34. W.H. Jiang and M. Atzmon: Rate dependence of serrated flow in a metallic glass. J. Mater. Res. 18, 755 (2003).

    Article  CAS  Google Scholar 

  35. A.L. Greer, A. Castellero, S.V. Madge, I.T. Walker, and J.R. Wilde: Nanoindentation studies of shear banding in fully amorphous and partially devitrified metallic alloys. Mater. Sci. Eng., A 375–377, 1182 (2004).

    Article  CAS  Google Scholar 

  36. C.A. Schuh, A.C. Lund, and T.G. Nieh: New regime of homogeneous flow in the deformation map of metallic glasses: Elevated temperature nanoindentation experiments and mechanistic modeling. Acta Mater. 52, 5879 (2004).

    Article  CAS  Google Scholar 

  37. B.C. Wei, L.C. Zhang, T.H. Zhang, D.M. Xing, J. Das, and J. Eckert: Strain rate dependence of plastic flow in Ce-based bulk metallic glass during nanoindentation. J. Mater. Res. 22, 258 (2007).

    Article  CAS  Google Scholar 

  38. B. Yang and T.G. Nieh: Effect of the nanoindentation rate on the shear band formation in an Au-based bulk metallic glass. Acta Mater. 55, 295 (2007).

    Article  CAS  Google Scholar 

  39. J-I. Jang, M.J. Lance, S. Wen, and G.M. Pharr: Evidence for nanoindentation-induced phase transformations in germanium. Appl. Phys. Lett. 86, 131907 (2005).

    Article  CAS  Google Scholar 

  40. J-I. Jang and G.M. Pharr: Influence of indenter angle on cracking in Si and Ge during nanoindentation. Acta Mater. 56, 4458 (2008).

    Article  CAS  Google Scholar 

  41. J-I. Jang, B-G. Yoo, and J-Y. Kim: Rate-dependent inhomogeneous-to-homogeneous transition of plastic flows during nanoindentation of bulk metallic glasses: Fact or artifact? Appl. Phys. Lett. 90, 211906 (2007).

    Google Scholar 

  42. B-G. Yoo, J-Y. Kim, and J-I. Jang: Influence of indenter geometry on the deformation behavior of Zr60Cu30A110 bulk metallic glass during nanoindentation. Mater. Trans. 48, 1765 (2007).

    Article  CAS  Google Scholar 

  43. L. Wang, S.X. Song, and T.G. Nieh: Assessing plastic shear resistance of bulk metallic glasses under nanoindentation. Appl. Phys. Lett. 92, 101925 (2008).

    Article  CAS  Google Scholar 

  44. H. Bei, S. Xie, and E.P. George: Softening caused by profuse shear banding in a bulk metallic glass. Phys. Rev. Lett. 96, 105503 (2006).

    Article  CAS  Google Scholar 

  45. S. Xie and E.P. George: Hardness and shear band evolution in bulk metallic glasses after plastic deformation and annealing. Acta Mater. 56, 5202 (2008).

    Article  CAS  Google Scholar 

  46. B-G. Yoo and J-I. Jang: A study on the evolution of subsurface deformation in a Zr-based bulk metallic glass during spherical indentation. J. Phys. D: Appl. Phys. 41, 074017 (2008).

    Article  CAS  Google Scholar 

  47. C. Tang, Y. Li, and K. Zeng: Characterization of mechanical properties of a Zr-based metallic glass by indentation techniques. Mater. Sci. Eng., A 384, 215 (2004).

    Article  CAS  Google Scholar 

  48. W.H. Li, T.H. Zhang, D.M. Xing, B.C. Wei, Y.R. Wang, and Y.D. Dong: Instrumented indentation study of plastic deformation in bulk metallic glasses. J. Mater. Res. 21, 75 (2006).

    Article  CAS  Google Scholar 

  49. D. Tabor: Hardness of Metals, 1st ed. (Clarendon Press, Oxford, UK, 1951).

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Jae-il Jang.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Yoo, BG., Park, KW., Lee, JC. et al. Role of free volume in strain softening of as-cast and annealed bulk metallic glass. Journal of Materials Research 24, 1405–1416 (2009). https://doi.org/10.1557/jmr.2009.0167

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1557/jmr.2009.0167

Navigation