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Fig. 1: Young’s, shear and bulk moduli.
Fig. 2: Total stiffness.

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Author information

Authors and Affiliations

  1. Materials Department, University of California, Santa Barbara, CA, USA

    J. B. Berger & R. M. McMeeking

  2. Department of Mechanical Engineering, University of California, Santa Barbara, CA, USA

    J. B. Berger & R. M. McMeeking

  3. Department of Materials Science and Engineering, School of Engineering and Applied Science, University of Virginia, Charlottesville, VA, USA

    H. N. G. Wadley

  4. School of Engineering, University of Aberdeen, King’s College, Aberdeen, UK

    R. M. McMeeking

  5. INM-Leibniz Institute for New Materials, Saarbrücken, Germany

    R. M. McMeeking

Authors
  1. J. B. Berger
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  2. H. N. G. Wadley
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  3. R. M. McMeeking
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Contributions

J.B.B. created the ideas, conceived and designed the new material geometries and performed the structural analysis. R.M.M. developed the analytical models for the strain energy and moduli and, with H.N.G.W., contributed to refining the concepts, contextualizing the results and providing critiques and assessments.

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Correspondence to J. B. Berger.

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Competing interests

The material geometry identified in this work to achieve the theoretical bounds in performance has been included in a Patent Cooperation Treaty (PCT/US2015/010458) by Nama Development, LLC (DE), which is majority-owned by J.B.B.

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Berger, J.B., Wadley, H.N.G. & McMeeking, R.M. Berger et al. reply. Nature 564, E2–E4 (2018). https://doi.org/10.1038/s41586-018-0725-7

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