Hostname: page-component-78c5997874-8bhkd Total loading time: 0 Render date: 2024-11-19T06:24:54.086Z Has data issue: false hasContentIssue false
  • English
  • Français

A critical examination of the paradox of strength and ductility in ultrafine-grained metals

Published online by Cambridge University Press:  07 October 2014

Tarang Mungole ,
Praveen Kumar ,
Megumi Kawasaki  and
Terence G. Langdon
Tarang Mungole
Affiliation:
Department of Materials Engineering, Indian Institute of Science, Bangalore 560012, India
Praveen Kumar*
Affiliation:
Department of Materials Engineering, Indian Institute of Science, Bangalore 560012, India
Megumi Kawasaki
Affiliation:
Division of Materials Science and Engineering, Hanyang University, Seoul 133-791, South Korea; and Departments of Aerospace & Mechanical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089-1453, USA
Terence G. Langdon
Affiliation:
Departments of Aerospace & Mechanical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089-1453, USA; and Materials Research Group, Faculty of Engineering and the Environment, University of Southampton, Southampton SO17 1BJ, UK
*
a)Address all correspondence to this author. e-mail: [email protected]
Get access

Abstract

The paradox of strength and ductility is now well established and denotes the difficulty of simultaneously achieving both high strength and high ductility. This paradox was critically examined using a cast Al–7%Si alloy processed by high-pressure torsion (HPT) for up to 10 turns at a temperature of either 298 or 445 K. This processing reduces the grain size to a minimum of ∼0.4 μm and also decreases the average size of the Si particles. The results show that samples processed to high numbers of HPT turns exhibit both high strength and high ductility when tested at relatively low strain rates and the strain rate sensitivity under these conditions is ∼0.14 which suggests that flow occurs by some limited grain boundary sliding and crystallographic slip. The results are also displayed on the traditional diagram for strength and ductility and they demonstrate the potential for achieving high strength and high ductility by increasing the number of turns in HPT.

Keywords

Al–Si alloyductilityhigh-pressure torsionstrengthultrafine grains
Type
Articles
Information
Journal of Materials Research , Volume 29 , Issue 21 , 14 November 2014 , pp. 2534 - 2546
Copyright
Copyright © Materials Research Society 2014 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Valiev, R.Z., Islamgaliev, R.K., and Alexandrov, I.V.: Bulk nanostructured materials from severe plastic deformation. Prog. Mater. Sci. 45, 103 (2000).Google Scholar
Langdon, T.G.: Twenty-five years of ultrafine-grained materials: Achieving exceptional properties through grain refinement. Acta Mater. 61, 7035 (2013).CrossRefGoogle Scholar
Valiev, R.Z., Estrin, Y., Horita, Z., Langdon, T.G., Zehetbauer, M.J., and Zhu, Y.T.: Producing bulk ultrafine-grained materials by severe plastic deformation. JOM 58(4), 33 (2006).CrossRefGoogle Scholar
Valiev, R.Z. and Langdon, T.G.: Principles of equal-channel angular pressing as a processing tool for grain refinement. Prog. Mater. Sci. 51, 881 (2006).CrossRefGoogle Scholar
Zhilyaev, A.P. and Langdon, T.G.: Using high-pressure torsion for metal processing: Fundamentals and applications. Prog. Mater. Sci. 53, 893 (2008).CrossRefGoogle Scholar
Zhilyaev, A.P., Lee, S., Nurislamova, G.V., Valiev, R.Z., and Langdon, T.G.: Microhardness and microstructural evolution in pure nickel during high-pressure torsion. Scr. Mater. 44, 2753 (2001).Google Scholar
Zhilyaev, A.P., Nurislamova, G.V., Kim, B.K., Baró, M.D., Szpunar, J.A., and Langdon, T.G.: Experimental parameters influencing grain refinement and microstructural evolution during high-pressure torsion. Acta Mater. 51, 753 (2003).Google Scholar
Wongsa-Ngam, J., Kawasaki, M., and Langdon, T.G.: A comparison of microstructures and mechanical properties in a Cu-Zr alloy processed using different SPD techniques. J. Mater. Sci. 48, 4653 (2013).Google Scholar
Hall, E.O.: The deformation and ageing of mild steel: III discussion of results. Proc. Phys. Soc. 64B, 747 (1951).Google Scholar
Petch, N.J.: The cleavage strength of polycrystals. J. Iron Steel Inst. 174, 25 (1953).Google Scholar
Valiev, R.: Materials science - Nanomaterial advantage. Nature 419, 887 (2002).Google Scholar
Valiev, R.: Nanostructuring of metals by severe plastic deformation for advanced properties. Nat. Mater. 3, 511 (2004).Google Scholar
Jia, D., Wang, Y.M., Ramesh, K.T., Ma, E., Zhu, Y.T., and Valiev, R.Z.: Deformation behavior and plastic instabilities of ultrafine-grained titanium. Appl. Phys. Lett. 79, 611 (2001).Google Scholar
Wang, Y.M. and Ma, E.: Strain hardening, strain rate sensitivity, and ductility of nanostructured metals. Mater. Sci. Eng., A 375–377, 46 (2004).Google Scholar
Koch, C.C., Morris, D.G., Lu, K., and Inoue, A.: Ductility of nanostructured materials. MRS Bull. 24(2), 54 (1999).Google Scholar
Wang, Y.M. and Ma, E.: Three strategies to achieve uniform tensile deformation in a nanostructured metal. Acta Mater. 52, 1699 (2004).Google Scholar
Ma, E.: Eight routes to improve the tensile ductility of bulk nanostructured metals and alloys. JOM 58(4), 49 (2006).Google Scholar
Zhao, Y.H., Bingert, J.F., Zhu, Y.T., Liao, X.Z., Valiev, R.Z., Horita, Z., Langdon, T.G., Zhou, Y.Z., and Lavernia, E.J.: Tougher ultrafine grain Cu via high-angle grain boundaries and low dislocation density. Appl. Phys. Lett. 92, 081903 (2008).CrossRefGoogle Scholar
Zhao, Y., Zhu, Y., and Lavernia, E.J.: Strategies for improving tensile ductility of bulk nanostructured materials. Adv. Eng. Mater. 12, 769 (2010).Google Scholar
Horita, Z., Ohashi, K., Fujita, T., Kaneko, K., and Langdon, T.G.: Achieving high strength and high ductility in precipitation-hardened alloys. Adv. Mater. 17, 1599 (2005).Google Scholar
Zhao, Y.H., Liao, X.Z., Cheng, S., Ma, E., and Zhu, Y.T.: Simultaneously increasing the ductility and strength of nanostructured alloys. Adv. Mater. 18, 2280 (2006).Google Scholar
Zhao, Y.H., Bingert, J.E., Liao, X.Z., Cui, B.Z., Han, K., Sergueeva, A.V., Mukherjee, A.K., Valiev, R.Z., Langdon, T.G., and Zhu, Y.T.T.: Simultaneously increasing the ductility and strength of ultra-fine-grained pure copper. Adv. Mater. 18, 2949 (2006).CrossRefGoogle Scholar
Zhao, Y.H., Topping, T., Bingert, J.F., Thornton, J.J., Dangelewicz, A.M., Li, Y., Liu, W., Zhu, Y.T., Zhou, Y., and Lavernia, E.J.: High tensile ductility and strength in bulk nanostructured nickel. Adv. Mater. 20, 3033 (2008).CrossRefGoogle Scholar
Höppel, H.W., Zhou, Z., Mughrabi, H., and Valiev, R.Z.: Microstructural study of the parameters governing coarsening and cyclic softening in fatigued ultrafine-grained copper. Philos. Mag. 82A, 1781 (2002).CrossRefGoogle Scholar
Vinogradov, A. and Hashimoto, S.: Fatigue of severely deformed metals. Adv. Eng. Mater. 5, 351 (2003).Google Scholar
Höppel, H.W., Kautz, M., Xu, C., Murashkin, M., Langdon, T.G., Valiev, R.Z., and Mughrabi, H.: An overview: Fatigue behaviour of ultrafine-grained metals and alloys. Int. J. Fatigue 28, 1001 (2006).Google Scholar
Valiev, R.Z., Alexandrov, I.V., Zhu, Y.T., and Lowe, T.C.: Paradox of strength and ductility in metals processed by severe plastic deformation. J. Mater. Res. 17, 5 (2002).CrossRefGoogle Scholar
Dalla Torre, F., Lapovok, R., Sandlin, J., Thomson, P.F., Davies, C.H.J., and Pereloma, E.V.: Microstructures and properties of copper processed by equal channel angular extrusion for 1-16 passes. Acta Mater. 52, 4819 (2004).CrossRefGoogle Scholar
Kumar, P., Xu, C., and Langdon, T.G.: Influence of strain rate on strength and ductility in an aluminum alloy processed by equal-channel angular pressing. J. Mater. Sci. 44, 3913 (2009).Google Scholar
Kaufman, J.G. and Roy, E.L.: Aluminum Casting Alloys. Properties, Processes and Applications (American Foundry Society, ASM International, Materials Park, OH, 2004).Google Scholar
Hafiz, M.F. and Kobayashi, T.: Tensile properties influencing variables in eutectic Al-Si casting alloys. Scr. Metall. Mater. 31, 701 (1994).Google Scholar
Hafiz, M.F. and Kobayashi, T.: Fracture toughness of eutectic Al-Si casting alloy with different microstructural features. J. Mater. Sci. 31, 6195 (1996).Google Scholar
García-Infanta, J.M., Swaminathan, S., Zhilyaev, A.P., Carreño, F., Ruano, O.A., and McNelley, T.R.: Microstructural development during equal channel angular pressing of hypo-eutectic Al-Si casting alloy by different processing routes. Mater. Sci. Eng., A 485, 160 (2008).Google Scholar
García-Infanta, J.M., Zhilyaev, A.P., Carreño, F., Ruano, O.A., Su, J.Q., Menon, S.K., and McNelley, T.R.: Strain path and microstructure evolution during severe deformation processing of an as-cast hypoeutectic Al-Si alloy. J. Mater. Sci. 45, 4613 (2010).Google Scholar
Zhilyaev, A.P., García-Infanta, J.M., Carreño, F., Langdon, T.G., and Ruano, O.A.: Particle and grain growth in an Al-Si alloy during high-pressure torsion. Scr. Mater. 57, 763 (2007).Google Scholar
Rajinikanth, V., Venkateswarlu, K., Sen, M.K., Das, M., Alhajeri, S.N., and Langdon, T.G.: Influence of scandium on an Al-2% Si alloy processed by high-pressure torsion. Mater. Sci. Eng., A 528, 1702 (2011).Google Scholar
Venkateswarlu, K., Rajinikanth, V., Alhajeri, S.N., and Langdon, T.G.: Application of high-pressure torsion to Al-Si alloys with and without scandium additions. Mater. Sci. Forum 667–669, 743 (2011).Google Scholar
Mungole, T., Nadammal, N., Dawra, K., Kumar, P., Kawasaki, M., and Langdon, T.G.: Evolution of microhardness and microstructure in a cast Al–7% Si alloy during high-pressure torsion. J. Mater. Sci. 48, 4671 (2013).Google Scholar
Figueiredo, R.B., Cetlin, P.R., and Langdon, T.G.: Using finite element modeling to examine the flow processes in quasi-constrained high-pressure torsion. Mater. Sci. Eng., A 528, 8198 (2011).CrossRefGoogle Scholar
Figueiredo, R.B., Pereira, P.H.R., Aguilar, M.T.P., Cetlin, P.R., and Langdon, T.G.: Using finite element modelling to examine the temperature distribution in quasi-constrained high-pressure torsion. Acta Mater. 60, 3190 (2012).CrossRefGoogle Scholar
Kawasaki, M. and Langdon, T.G.: The significance of strain reversals during processing by high-pressure torsion. Mater. Sci. Eng., A 498, 341 (2008).Google Scholar
Valiev, R.Z., Ivanisenko, Y.V., Rauch, E.F., and Baudelet, B.: Structure and deformation behaviour of armco iron subjected to severe plastic deformation. Acta Mater. 44, 4705 (1996).Google Scholar
Wetscher, F., Vorhauer, A., Stock, R., and Pippan, R.: Structural refinement of low alloyed steels during severe plastic deformation. Mater. Sci. Eng., A 387–389, 809 (2004).Google Scholar
Wetscher, F., Pippan, R., Sturm, S., Kauffmann, F., Scheu, C., and Dehm, G.: TEM investigations of the structural evolution in a pearlitic steel deformed by high-pressure torsion. Metall. Mater. Trans. A 37, 1963 (2006).Google Scholar
Estrin, Y., Molotnikov, A., Davies, C.H.J., and Lapovok, R.: Strain gradient plasticity modelling of high-pressure torsion. J. Mech. Phys. Solids 56, 1186 (2008).Google Scholar
Loucif, A., Figueiredo, R.B., Kawasaki, M., Baudin, T., Brisset, F., Chemam, R., and Langdon, T.G.: Effect of aging on microstructural development in an Al–Mg–Si alloy processed by high-pressure torsion. J. Mater. Sci. 47, 7815 (2012).CrossRefGoogle Scholar
Zhao, Y.H., Guo, Y.Z., Wei, Q., Dangelewicz, A.M., Xu, C., Zhu, Y.T., Langdon, T.G., Zhou, Y.Z., and Lavernia, E.J.: Influence of specimen dimensions on the tensile behavior of ultrafine-grained Cu. Scr. Mater. 59, 627 (2008).Google Scholar
Zhao, Y.H., Guo, Y.Z., Wei, Q., Topping, T.D., Dangelewicz, A.M., Zhu, Y.T., Langdon, T.G., and Lavernia, E.J.: Influence of specimen dimensions and strain measurement methods on tensile stress-strain curves. Mater. Sci. Eng., A 525, 68 (2009).Google Scholar
Eaton, P. and West, P.: Atomic Force Microscopy (Oxford University Press, New York, NY, 2010).Google Scholar
Langdon, T.G.: An evaluation of the strain contributed by grain boundary sliding in superplasticity. Mater. Sci. Eng., A 174A, 225 (1994).Google Scholar
Langdon, T.G.: Seventy-five years of superplasticity: Historic developments and new opportunities. J. Mater. Sci. 44, 5998 (2009).Google Scholar
Gifkins, R.C. and Langdon, T.G.: On the question of low-temperature sliding at grain boundaries. J. Inst. Met. 93, 347 (1965).Google Scholar
Langdon, T.G.: Grain boundary sliding revisited: Developments in sliding over four decades. J. Mater. Sci. 41, 597 (2006).Google Scholar
Van Swygenhoven, H. and Caro, A.: Plastic behavior of nanophase Ni: A molecular dynamics computer simulation. Appl. Phys. Lett. 71, 1652 (1997).Google Scholar
Schiøtz, J., Di Tolla, F.D., and Jacobsen, K.W.: Softening of nanocrystalline metals at very small grain sizes. Nature 391, 561 (1998).Google Scholar
Van Swygenhoven, H., Spaczer, M., Caro, A., and Farkas, D.: Competing plastic deformation mechanisms in nanophase metals. Phys. Rev. B 60, 22 (1999).Google Scholar
Van Swygenhoven, H. and Derlet, P.M.: Grain-boundary sliding in nanocrystalline FCC metals. Phys. Rev. B 64, 224105 (2001).CrossRefGoogle Scholar
Kumar, K.S., Van Swygenhoven, H., and Suresh, S.: Mechanical behavior of nanocrystalline metals and alloys. Acta Mater. 51, 5743 (2003).Google Scholar
Valiev, R.Z., Kozlov, E.V., Ivanov, Y.F., Lian, J., Nazarov, A.A., and Baudelet, B.: Deformation-behavior of ultra-fine-grained copper. Acta Metall. Mater. 42, 2467 (1994).Google Scholar
Chinh, N.Q., Vörös, G., Szommer, P., Horita, Z., and Langdon, T.G.: Grain boundary sliding as a significant mechanism of low temperature plastic deformation in ECAP aluminum. Mater. Sci. Forum 503–504, 1001 (2006).CrossRefGoogle Scholar
Chinh, N.Q., Szommer, P., Horita, Z., and Langdon, T.G.: Experimental evidence for grain boundary sliding in ultrafine-grained aluminum processed by severe plastic deformation. Adv. Mater. 18, 34 (2006).Google Scholar
Valiev, R.Z., Yu Murashkin, M., Kilmametov, A., Straumal, B., Chinh, N.Q., and Langdon, T.G.: Unusual super-ductility at room temperature in an ultrafine-grained aluminum alloy. J. Mater. Sci. 45, 4718 (2010).Google Scholar
Chinh, N.Q., Csanádi, T., Gubicza, J., Valiev, R.Z., Straumal, B.B., and Langdon, T.G.: The effect of grain boundary sliding and strain rate sensitivity on the ductility of ultrafine-grained materials. Mater. Sci. Forum 667–669, 677 (2011).Google Scholar
Chinh, N.Q., Györi, T., Valiev, R.Z., Szommer, P., Varga, G., Havancsák, K., and Langdon, T.G.: Observations of unique plastic behavior in micro-pillars of an ultrafine-grained alloy. MRS Commun. 2, 75 (2012).Google Scholar
Polyakov, A.V., Semenova, I.P., Valiev, R.Z., Huang, Y., and Langdon, T.G.: Influence of annealing on ductility of ultrafine-grained titanium processed by ECAP-conform and drawing. MRS Commun. 3, 249 (2013).Google Scholar
Valiev, R.Z., Korznikov, A.V., and Mulyukov, R.R.: Structure and properties of ultrafine-grained materials produced by severe plastic deformation. Mater. Sci. Eng., A 168, 141 (1993).Google Scholar
Horita, Z., Smith, D.J., Furukawa, M., Nemoto, M., Valiev, R.Z., and Langdon, T.G.: An investigation of grain boundaries in submicrometer-grained Al-Mg solid solution alloys using high-resolution electron microscopy. J. Mater. Res. 11, 1880 (1996).Google Scholar
Horita, Z., Smith, D.J., Nemoto, M., Valiev, R.Z., and Langdon, T.G.: Observations of grain boundary structure in submicrometer-grained Cu and Ni using high-resolution electron microscopy. J. Mater. Res. 13, 446 (1998).CrossRefGoogle Scholar
Kawasaki, M., Horita, Z., and Langdon, T.G.: Microstructural evolution in high purity aluminum processed by ECAP. Mater. Sci. Eng., A 524, 143 (2009).Google Scholar
Xu, C., Horita, Z., and Langdon, T.G.: Microstructural evolution in an aluminum solid solution alloy processed by ECAP. Mater. Sci. Eng., A 528, 6059 (2011).CrossRefGoogle Scholar
Loucif, A., Baudin, T., Figueiredo, R.B., Brisset, F., Helbert, A.L., Chemam, R., and Langdon, T.G.: Microstructure and microtexture evolution with aging treatment in an Al-Mg-Si alloy severely deformed by HPT. J. Mater. Sci. 48, 4573 (2013).Google Scholar
Langdon, T.G.: A unified approach to grain boundary sliding in creep and superplasticity. Acta Metall. Mater. 42, 2437 (1994).Google Scholar
Wang, Y.M., Chen, M.W., Zhou, F.H., and Ma, E.: High tensile ductility in a nanostructured metal. Nature 419, 912 (2002).Google Scholar
Witkin, D., Lee, Z., Rodriguez, R., Nutt, S., and Lavernia, E.: Al-Mg alloy engineered with bimodal grain size for high strength and increased ductility. Scr. Mater. 49, 297 (2003).Google Scholar
Han, B.Q., Mohamed, F.A., Bampton, C.C., and Lavernia, E.J.: Improvement of toughness and ductility of a cryomilled Al-Mg alloy via microstructural modification. Metall. Mater. Trans. A 36, 2081 (2005).Google Scholar
Yang, K., Fecht, H-J., and Ivanisenko, Y.: First direct in situ observation of grain boundary sliding in ultrafine grained noble metal. Adv. Eng. Mater. 16, 517 (2014).Google Scholar