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Cast aluminium single crystals cross the threshold from bulk to size-dependent stochastic plasticity

Nature Materials volume 16, pages 730–736 (2017)Cite this article

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Abstract

Metals are known to exhibit mechanical behaviour at the nanoscale different to bulk samples. This transition typically initiates at the micrometre scale, yet existing techniques to produce micrometre-sized samples often introduce artefacts that can influence deformation mechanisms. Here, we demonstrate the casting of micrometre-scale aluminium single-crystal wires by infiltration of a salt mould. Samples have millimetre lengths, smooth surfaces, a range of crystallographic orientations, and a diameter D as small as 6 μm. The wires deform in bursts, at a stress that increases with decreasing D. Bursts greater than 200 nm account for roughly 50% of wire deformation and have exponentially distributed intensities. Dislocation dynamics simulations show that single-arm sources that produce large displacement bursts halted by stochastic cross-slip and lock formation explain microcast wire behaviour. This microcasting technique may be extended to several other metals or alloys and offers the possibility of exploring mechanical behaviour spanning the micrometre scale.

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Figure 1: Casting process and resulting cast wires.
Figure 2: Microcast aluminium tensile curves and the size effect.
Figure 3: Simulated tensile curves in resolved coordinates.
Figure 4: Slip steps on deformed cast Al microwires.
Figure 5: Distributions of displacement burst sizes and underlying mechanisms.

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References

  1. Kubin, L. P. Dislocations, Mesoscale Simulations and Plastic Flow 307 (Oxford Univ. Press, 2013).

    Book  Google Scholar 

  2. Uchic, M. D., Shade, P. A. & Dimiduk, D. M. Plasticity of micrometer-scale single crystals in compression. Annu. Rev. Mater. Res. 39, 361–386 (2009).

    Article  CAS  Google Scholar 

  3. Greer, J. R. & De Hosson, J. T. M. Plasticity in small-sized metallic systems: intrinsic versus extrinsic size effect. Prog. Mater. Sci. 56, 654–724 (2011).

    Article  CAS  Google Scholar 

  4. Kraft, O., Gruber, P. A., Moenig, R. & Weygand, D. Plasticity in confined dimensions. Annu. Rev. Mater. Res. 40, 293–317 (2010).

    Article  CAS  Google Scholar 

  5. Dehm, G. Miniaturized single-crystalline fcc metals deformed in tension: new insights in size-dependent plasticity. Prog. Mater. Sci. 54, 664–688 (2009).

    Article  CAS  Google Scholar 

  6. Weinberger, C. R. & Cai, W. Plasticity of metal nanowires. J. Mater. Chem. 22, 3277–3292 (2012).

    Article  CAS  Google Scholar 

  7. Huetsch, J. & Lilleodden, E. T. The influence of focused-ion beam preparation technique on microcompression investigations: lathe vs. annular milling. Scr. Mater. 77, 49–51 (2014).

    Article  Google Scholar 

  8. Volkert, C. A. & Minor, A. M. Focused ion beam microscopy and micromachining. MRS Bull. 32, 389–395 (2007).

    Article  CAS  Google Scholar 

  9. Bei, H., Shim, S., Miller, M. K., Pharr, G. M. & George, E. P. Effects of focused ion beam milling on the nanomechanical behavior of a molybdenum-alloy single crystal. Appl. Phys. Lett. 91, 111915 (2007).

    Article  Google Scholar 

  10. Kiener, D., Motz, C., Rester, M., Jenko, M. & Dehm, G. FIB damage of Cu and possible consequences for miniaturized mechanical tests. Mater. Sci. Eng. 459, 262–272 (2007).

    Article  Google Scholar 

  11. Shim, S., Bei, H., Miller, M. K., Pharr, G. M. & George, E. P. 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, 503–510 (2009).

    Article  CAS  Google Scholar 

  12. Mompiou, F. et al. Source-based strengthening of sub-micrometer Al fibers. Acta Mater. 60, 977–983 (2012).

    Article  CAS  Google Scholar 

  13. Johanns, K. E. et al. In-situ tensile testing of single-crystal molybdenum alloy fibers with various dislocation densities in a scanning electron microscope. J. Mater. Res. 27, 508–520 (2012).

    Article  CAS  Google Scholar 

  14. Chisholm, C. et al. Dislocation starvation and exhaustion hardening in Mo alloy nanofibers. Acta Mater. 60, 2258–2264 (2012).

    Article  CAS  Google Scholar 

  15. Rao, S. I. et al. Athermal mechanisms of size-dependent crystal flow gleaned from three-dimensional discrete dislocation simulations. Acta Mater. 56, 3245–3259 (2008).

    Article  CAS  Google Scholar 

  16. Baumeister, G., Buqezi-Ahmeti, D., Glaser, J. & Ritzhaupt-Kleissl, H. J. New approaches in microcasting: permanent mold casting and composite casting. Microsyst. Technol. 17, 289–300 (2011).

    Article  CAS  Google Scholar 

  17. Rögner, J., Lang, K. H., Baumeister, G. & Schulze, V. Microstructure and mechanical properties of micro tensile specimens made of CuAl10Ni5Fe4 produced by micro casting. Microsyst. Technol. 17, 301–311 (2011).

    Article  Google Scholar 

  18. Tabata, T., Fujita, H., Yamamoto, S. & Cyoji, T. Effect of specimen diameter on tensile behaviors of aluminum thin wires. J. Phys. Soc. Jpn 40, 792–797 (1976).

    Article  CAS  Google Scholar 

  19. Ng, K. S. & Ngan, A. H. W. Stochastic nature of plasticity of aluminum micro-pillars. Acta Mater. 56, 1712–1720 (2008).

    Article  CAS  Google Scholar 

  20. Rao, S. I. et al. Atomistic simulations of cross-slip nucleation at screw dislocation intersections in face-centered cubic nickel. Philos. Mag. 89, 3351–3369 (2009).

    Article  CAS  Google Scholar 

  21. Hussein, A. M., Rao, S. I., Uchic, M. D., Dimiduk, D. M. & El-Awady, J. A. Microstructurally based cross-slip mechanisms and their effects on dislocation microstructure evolution in fcc crystals. Acta Mater. 85, 180–190 (2015).

    Article  CAS  Google Scholar 

  22. Dimiduk, D. M., Woodward, C., LeSar, R. & Uchic, M. D. Scale-free intermittent flow in crystal plasticity. Science 312, 1188–1190 (2006).

    Article  CAS  Google Scholar 

  23. Kiener, D., Grosinger, W., Dehm, G. & Pippan, R. A further step towards an understanding of size-dependent crystal plasticity: in situ tension experiments of miniaturized single-crystal copper samples. Acta Mater. 56, 580–592 (2008).

    Article  CAS  Google Scholar 

  24. Csikor, F. F., Motz, C., Weygand, D., Zaiser, M. & Zapperi, S. Dislocation avalanches, strain bursts, and the problem of plastic forming at the micrometer scale. Science 318, 251–254 (2007).

    Article  CAS  Google Scholar 

  25. Devincre, B. & Kubin, L. Scale transitions in crystal plasticity by dislocation dynamics simulations. C. R. Phys. 11, 274–284 (2010).

    Article  CAS  Google Scholar 

  26. Richeton, T., Dobron, P., Chmelik, F., Weiss, J. & Louchet, F. On the critical character of plasticity in metallic single crystals. Mater. Sci. Eng. A 424, 190–195 (2006).

    Article  Google Scholar 

  27. Weiss, J. et al. Evidence for universal intermittent crystal plasticity from acoustic emission and high-resolution extensometry experiments. Phys. Rev. B 76, 224110 (2007).

    Article  Google Scholar 

  28. Zaiser, M. & Moretti, P. Fluctuation phenomena in crystal plasticity - a continuum model. J. Stat. Mech. Theor. Exp. 2005, P08004 (2005).

    Article  Google Scholar 

  29. Zaiser, M. & Nikitas, N. Slip avalanches in crystal plasticity: scaling of the avalanche cut-off. J. Stat. Mech. Theor. Exp. 2007, P04013 (2007).

    Article  Google Scholar 

  30. Motz, C., Weygand, D., Senger, J. & Gumbsch, P. Initial dislocation structures in 3D-discrete dislocation dynamics and their influence on microscale plasticity. Acta Mater. 57, 1744–1754 (2009).

    Article  CAS  Google Scholar 

  31. Staubwasser, W. On work-hardening of aluminium-single crystals (99.99-percent) and its interpretation. Acta Metall. 7, 43–50 (1959).

    Article  CAS  Google Scholar 

  32. Diologent, F., Goodall, R. & Mortensen, A. Surface oxide in replicated microcellular aluminium and its influence on the plasticity size effect. Acta Mater. 57, 286–294 (2009).

    CAS  Google Scholar 

  33. Kiener, D. et al. Influence of external and internal length scale on the flow stress of copper. Int. J. Mater. Res. 98, 1047–1053 (2007).

    Article  CAS  Google Scholar 

  34. Dieter, G. E. Mechanical Metallurgy 128 (McGraw-Hill, 1988).

    Google Scholar 

  35. Murr, L. E. Interfacial Phenomena in Metals and Alloys (Addison-Wesley, 1975).

    Google Scholar 

  36. Arsenlis, A. et al. Enabling strain hardening simulations with dislocation dynamics. Modelling Simul. Mater. Sci. Eng. 15, 553–595 (2007).

    Article  Google Scholar 

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Acknowledgements

The experimental part of this work was sponsored by the Swiss National Science Foundation, Contract No 200020_156064/1. Part of the computations were supported by a grant of computer time from the DOD High Performance Computing Modernization Program, at the Aeronautical Systems Center/Major Shared Resource Center, USA. S.I.R. and W.A.C. acknowledge support of this work through a European Research Council Advanced Grant, ‘Predictive Computational Metallurgy’, ERC grant agreement no. 339081—PreCoMet. The authors wish to thank L. Kubin of the CNRS in France for frequent and helpful advice over the course of this project, H. van Swygenhoven, K. Hemker, O. Kraft, M. Legros, D. Weygand and P. Gumbsch for stimulating discussions, together with W. Dufour, C. Bacciarini, R. Charvet and C. Dénéréaz at EPFL for their contributions in designing and building the microtesting apparatus. We thank M. Cantoni and E. Oveisi at EPFL’s Interdisciplinary Center for Electron Microscopy (CIME) for their substantial contributions in producing electron micrographs in the Supplementary Information of this article and last but not least K. Schenk at EPFL who kindly measured the orientation of our wires using monocrystalline diffraction.

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Authors and Affiliations

  1. Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne CH-1015, Switzerland

    J. Krebs, S. I. Rao, S. Verheyden, C. Miko, R. Goodall, W. A. Curtin & A. Mortensen

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  1. J. Krebs
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Contributions

J.K. and S.V. performed the experiments and produced all the experimental data; J.K., C.M., R.G. and A.M. developed the microcasting process; S.I.R. and W.A.C. conducted all the 3D dislocation dynamics simulations; J.K., S.I.R., W.A.C. and A.M. wrote the text; J.K., S.V., S.I.R., R.G. and A.M. produced figures; S.I.R. produced the films; J.K., S.I.R., S.V., W.A.C. and A.M. interpreted and discussed the results.

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Correspondence to J. Krebs or S. I. Rao.

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Krebs, J., Rao, S., Verheyden, S. et al. Cast aluminium single crystals cross the threshold from bulk to size-dependent stochastic plasticity. Nature Mater 16, 730–736 (2017). https://doi.org/10.1038/nmat4911

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