Fracture toughness and auxeticity in disordered metamaterials

Fracture toughness and auxeticity in disordered metamaterials | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Fracture toughness and auxeticity in disordered metamaterials Hannes Holey, Andrea Lorenzo Henri Sergio Detry, Silvia Bonfanti, and 6 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7327709/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Auxetic metamaterials are commonly thought to exhibit favorable mechanical properties, notably high energy absorption. Here we investigate disordered metamaterials obtained from random beam networks by optimizing simultaneously auxeticity and the energy absorbed before fracture. By giving different weights to these optimization targets, we demonstrate that the optimal configurations are connected along a Pareto front where high auxeticity implies comparatively low energy absorption and vice versa. We study the mechanical properties of the resulting metamaterials and characterize the different deformation modes obtained for distinct optimization targets. The simulation and optimization results are validated by comparison with the deformation behavior of additively manufactured samples. Our work provides an illustration of the potentials and limitations of multi-objective optimization in the design of disordered mechanical metamaterials. Materials Engineering metamaterials auxeticity fracture energy optimization Full Text Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7327709","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":497732632,"identity":"dbea6a5b-c5bb-434a-b446-d23bc7133902","order_by":0,"name":"Hannes Holey","email":"","orcid":"","institution":"Universita di Milano","correspondingAuthor":false,"prefix":"","firstName":"Hannes","middleName":"","lastName":"Holey","suffix":""},{"id":497732633,"identity":"e027c47b-4c92-4375-982b-efa3ab0c2f17","order_by":1,"name":"Andrea Lorenzo Henri Sergio Detry","email":"","orcid":"","institution":"Universita di Milano","correspondingAuthor":false,"prefix":"","firstName":"Andrea","middleName":"Lorenzo Henri Sergio","lastName":"Detry","suffix":""},{"id":497732634,"identity":"b0fe1520-0e49-4a1a-bd62-eb3fd4d67c2c","order_by":2,"name":"Silvia Bonfanti","email":"","orcid":"","institution":"NOMATEN Centre of Excellence, National Center for Nuclear Research","correspondingAuthor":false,"prefix":"","firstName":"Silvia","middleName":"","lastName":"Bonfanti","suffix":""},{"id":497732635,"identity":"d6a6fa56-7e85-4695-bba1-3ecfa4563488","order_by":3,"name":"Roberto Guerra","email":"","orcid":"","institution":"Universita di Milano","correspondingAuthor":false,"prefix":"","firstName":"Roberto","middleName":"","lastName":"Guerra","suffix":""},{"id":497732636,"identity":"1770082f-da94-4bd2-b129-e19a1e91aa4c","order_by":4,"name":"Anshul D. 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