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Heterogeneous dislocation nucleation from surfaces and interfaces as governing plasticity mechanism in nanoscale metals

  • Andrew T. Jennings (a1) and Julia R. Greer (a1)

We report the results of constant strain rate experiments on electroplated, single crystalline copper pillars with diameters between 75 and 525 nm. At slow strain rates, 10−3 s−1, pillar diameters with 150 nm and above show a size-dependent strength similar to previous reports. Below 150 nm, we find that the size effect vanishes as the strength transitions to a relatively size-independent regime. Strain rate sensitivity and activation volume are determined from uniaxial compression tests at different strain rates and corroborate a deformation mechanism change. These results are discussed in the framework of recent in situ transmission electron microscopy experiments observing two distinct deformation mechanisms in pillars and thin films on flexible substrates: partial dislocation nucleation from stress concentrations in smaller structures and single arm source operation in larger samples. Models attempting to explain these different size-dependent regimes are discussed in relation to these experiments and existing literature revealing further insights into the likely small-scale deformation mechanisms.

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2.E.O. Hall : The deformation and ageing of mild steel. 3. Discussion of results. Proc. Phys. Soc. London, Sect. B 64, 747 (1951).

4.G. Dehm : Miniaturized single-crystalline fcc metals deformed in tension: New insights in size-dependent plasticity. Prog. Mater. Sci. 54, 664 (2009).

7.J.R. Greer and J.T.M. De Hosson : Review: Plasticity in small-sized metallic systems: Intrinsic versus extrinsic size effect. Prog. Mater. Sci. 56, 654 (2011).

8.W.D. Nix , J.R. Greer , G. Feng , and E.T. Lilleodden : Deformation at the nanometer and micrometer length scales: Effects of strain gradients and dislocation starvation. Thin Solid Films 515, 3152 (2007).

9.D.M. Dimiduk , M.D. Uchic , and T.A. Parthasarathy : Size-affected single-slip behavior of pure nickel microcrystals. Acta Mater. 53, 4065 (2005).

11.J.R. Greer , W.C. Oliver , and W.D. Nix : Size dependence of mechanical properties of gold at the micron scale in the absence of strain gradients. Acta Mater. 53, 1821 (2005).

13.P.A. Gruber , C. Solenthaler , E. Arzt , and R. Spolenak : Strong single-crystalline Au films tested by a new synchrotron technique. Acta Mater. 56, 1876 (2008).

14.S.H. Oh , M. Legros , D. Kiener , P. Gruber , and G. Dehm : In situ TEM straining of single crystal Au films on polyimide: Change of deformation mechanisms at the nanoscale. Acta Mater. 55, 5558 (2007).

15.T.A. Parthasarathy , S.I. Rao , D.M. Dimiduk , M.D. Uchic , and D.R. Trinkle : Contribution to size effect of yield strength from the stochastics of dislocation source lengths in finite samples. Scr. Mater. 56, 313 (2007).

16.S. Rao , D. Dimiduk , M. Tang , T. Parthasarathy , M. Uchic , and C. Woodward : Estimating the strength of single-ended dislocation sources in micron-sized single crystals. Philos. Mag. 87, 4777 (2007).

18.D.M. Norfleet , D.M. Dimiduk , S.J. Polasik , M.D. Uchic , and M.J. Mills : Dislocation structures and their relationship to strength in deformed nickel microcrystals. Acta Mater. 56, 2988 (2008).

23.J. Senger , D. Weygand , P. Gumbsch , and O. Kraft : Discrete dislocation simulations of the plasticity of micro-pillars under uniaxial loading. Scr. Mater. 58, 587 (2008).

25.A.T. Jennings , J. Li , and J.R. Greer : Emergence of strain rate sensitivity in Cu nano-pillars: Transition from dislocation multiplication to dislocation nucleation. Acta Mater. 59, 5627 (2011).

26.G. Richter , K. Hillerich , D.S. Gianola , R. Mönig , O. Kraft , and C.A. Volkert : Ultrahigh strength single crystalline nanowhiskers grown by physical vapor deposition. Nano Lett. 9, 3048 (2009).

27.H. Zheng , A. Cao , C. Weinberger , J.Y. Huang , K. Du , J. Wang , Y. Ma , Y. Xia , and S.X. Mao : Discrete plasticity in sub-10-nm-sized gold crystals. Nat. Commun. 1, 144 (2010).

30.M.J. Burek and J.R. Greer : Fabrication and microstructure control of nanoscale mechanical testing specimens via electron beam lithography and electroplating. Nano Lett. 10, 69 (2010).

31.A.T. Jennings , M.J. Burek , and J.R. Greer : Microstructure versus size: Mechanical properties of electroplated single crystalline Cu nanopillars. Phys. Rev. Lett. 104, 135503 (2010).

32.A.T. Jennings and J.R. Greer : Tensile deformation of electroplated copper nanopillars. Philos. Mag. 91, 1108 (2011).

33.H. Bei , S. Shim , E.P. George , M.K. Miller , E.G. Herbert , and G.M. Pharr : Compressive strengths of molybdenum alloy micro-pillars prepared using a new technique. Scr. Mater. 57, 397 (2007).

35.S. Shim , H. Bei , M.K. Miller , G.M. Pharr , and E.P. George : Effects of focused-ion-beam milling on the compressive behavior of directionally solidified micropillars and the nanoindentation response of an electropolished surface. Acta Mater. 57, 503 (2009).

37.M. Dietiker , S. Buzzi , G. Pigozzi , J.F. Loffler , and R. Spolenak : Deformation behavior of gold nano-pillars prepared by nanoimprinting and focused-ion-beam milling. Acta Mater. 59, 2180 (2011).

39.M.B. Lowry , D. Kiener , M.M. LeBlanc , C. Chisholm , J.N. Florando , J.W. Morris , and A.M. Minor : Achieving the ideal strength in annealed molybdenum nanopillars. Acta Mater. 58, 5160 (2010).

40.J.R. Greer , D.C. Jang , J.Y. Kim , and M.J. Burek : Emergence of new mechanical functionality in materials via size reduction. Adv. Funct. Mater. 19, 2880 (2009).

42.W.D. Nix and S.W. Lee : Micro-pillar plasticity controlled by dislocation nucleation at surfaces. Philos. Mag. 91, 1084 (2011).

43.K.S. Ng and A.H.W. Ngan : Stochastic theory for jerky deformation in small crystal volumes with pre-existing dislocations. Philos. Mag. 88, 677 (2008).

44.S.S. Brenner : Tensile strength of whiskers. J. Appl. Phys. 27, 1484 (1956).

45.Y. Lu , J.Y. Huang , C. Wang , S.H. Sun , and J. Lou : Cold welding of ultrathin gold nanowires. Nat. Nanotechnol. 5, 218 (2010).

46.Z.W. Shan , R.K. Mishra , S.A. Syed Asif , O.L. Warren , and A.M. Minor : Mechanical annealing and source-limited deformation in submicrometre-diameter Ni crystals. Nat. Mater. 7, 115 (2008).

47.C.R. Weinberger and W. Cai : Surface-controlled dislocation multiplication in metal micropillars. Proc. Natl. Acad. Sci. USA 105, 14304 (2008).

49.L.B. Freund : The stability of a dislocation threading a strained layer on a substrate. J. Appl. Mech. 54, 553 (1987).

50.J.R. Greer and W.D. Nix : Nanoscale gold pillars strengthened through dislocation starvation. Phys. Rev. B 73, 245410 (2006).

51.M.W. Chen , E. Ma , K.J. Hemker , H.W. Sheng , Y.M. Wang , and X.M. Cheng : Deformation twinning in nanocrystalline aluminum. Science 300, 1275 (2003).

52.S. Aubry , K. Kang , S. Ryu , and W. Cai : Energy barrier for homogeneous dislocation nucleation: Comparing atomistic and continuum models. Scr. Mater. 64, 1043 (2011).

55.Y. Estrin , H.S. Kim , and F.R.N. Nabarro : A comment on the role of Frank-Read sources in plasticity of nanomaterials. Acta Mater. 55, 6401 (2007).

58.T. Zhu and J. Li : Ultra-strength materials. Prog. Mater. Sci. 55, 710 (2010).

60.H. Van Swygenhoven , P.M. Derlet , and A.G. Froseth : Stacking fault energies and slip in nanocrystalline metals. Nat. Mater. 3, 399 (2004).

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Journal of Materials Research
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