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Strength through defects: A novel Bayesian approach for the optimization of architected materials

Vangelatos, Zacharias and Sheikh, Haris Moazam and Marcus, Philip S. and Grigoropoulos, Costas P. and Lopez, Victor Z. and Flamourakis, George and Farsari, Maria (2021) Strength through defects: A novel Bayesian approach for the optimization of architected materials. Science Advances, 7 (41). Art. No. eabk2218. ISSN 2375-2548. PMCID PMC8500519. doi:10.1126/sciadv.abk2218.

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We use a previously unexplored Bayesian optimization framework, “evolutionary Monte Carlo sampling,” to systematically design the arrangement of defects in an architected microlattice to maximize its strain energy density before undergoing catastrophic failure. Our algorithm searches a design space with billions of 4 × 4 × 5 3D lattices, yet it finds the global optimum with only 250 cost function evaluations. Our optimum has a normalized strain energy density 12,464 times greater than its commonly studied defect-free counterpart. Traditional optimization is inefficient for this microlattice because (i) the design space has discrete, qualitative parameter states as input variables, (ii) the cost function is computationally expensive, and (iii) the design space is large. Our proposed framework is useful for architected materials and for many optimization problems in science and elucidates how defects can enhance the mechanical performance of architected materials.

Item Type:Article
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URLURL TypeDescription CentralArticle
Vangelatos, Zacharias0000-0001-9513-3671
Grigoropoulos, Costas P.0000-0002-8505-4037
Flamourakis, George0000-0003-3695-014X
Farsari, Maria0000-0003-2435-4156
Additional Information:© 2021 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC). Submitted 2 July 2021; Accepted 17 August 2021; Published 8 October 2021. We thank K. Komvopoulos (Department of Mechanical Engineering) and U. Seljak [Department of Physics, University of California at Berkeley (UCB)] for insightful discussions, P. Hosemann [Department of Nuclear Engineering (UCB)] for the use of the nanoindentation apparatus, F. Allen [Department of Materials Science and Engineering (UCB)] for training to use the helium ion microscope, and S. Govindjee and F. Armero [Department of Civil and Environmental Engineering (UCB)] and D. J. Steigmann [Department of Mechanical Engineering (UCB)] for fruitful discussions regarding the mechanical performance of the structures. This work is suppoted by the Extreme Science and Engineering Discovery Environment (XSEDE), supported by NSF grant number ACI-1548562 through allocation TG-CTS190047 (H.M.S. and P.S.M.); NSF Scalable Nanomanufacturing Program, award no. 1449305 (C.P.G. and Z.V.); The California Institute of Quantitative Bioscience, QB3 Lab (C.P.G. and Z.V.); and Lotusland Investment Holdings Inc. and Bohn Valley Inc. (financial gift; H.M.S. and P.S.M.). Authors contributions: Conceptualization: Z.V. and H.M.S. Methodology: H.M.S., Z.V., P.S.M., and C.P.G. Investigation: Z.V., H.M.S., V.Z.L., and G.F. Visualization: Z.V., H.M.S., P.S.M., and C.P.G. Supervision: C.P.G., P.S.M., and M.F. Writing (original draft): Z.V., H.M.S., and P.S.M. Writing (review and editing): Z.V., H.M.S., P.S.M., and C.P.G. The authors declare that they have no competing interests. Data and materials availability: The data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials.
Funding AgencyGrant Number
California Institute of Quantitative BioscienceUNSPECIFIED
Lotusland Investment Holdings Inc.UNSPECIFIED
Issue or Number:41
PubMed Central ID:PMC8500519
Record Number:CaltechAUTHORS:20211011-175305271
Persistent URL:
Official Citation:Z. Vangelatos, H. M. Sheikh, P. S. Marcus, C. P. Grigoropoulos, V. Z. Lopez, G. Flamourakis, M. Farsari, Strength through defects: A novel Bayesian approach for the optimization of architected materials. Sci. Adv. 7, eabk2218 (2021); DOI: 10.1126/sciadv.abk2218
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:111353
Deposited By: Tony Diaz
Deposited On:11 Oct 2021 18:09
Last Modified:18 Oct 2021 23:45

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