The effects of fission vs fusion-like neutron spectra on REBCO activation and microstructure

The effects of fission vs fusion-like neutron spectra on REBCO activation and microstructure | 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 Article The effects of fission vs fusion-like neutron spectra on REBCO activation and microstructure Christopher Reis, Edward Kinyon, Matthew Martel, Yuxin Hu, Felix Pat, and 20 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8888914/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 REBCO-based superconducting magnets are considered crucial to the long-awaited realization of commercially viable controlled thermonuclear fusion via compact reactor architectures. To expand the current understanding of how the inherently reduced shielding of these proposed designs affects the radiation-sensitive high temperature superconductors, the activation spectra and microstructure of REBCO tapes irradiated more traditionally with fission-reactor neutrons were compared to those irradiated with the higher-fidelity fusion-like spectrum produced by thick target deuteron breakup in a first-of-its-kind irradiation experiment on these coated conductors. For the fusion-like case, several peaks in the activation spectrum confirmed high-threshold nuclear reactions, and SEM revealed superficial alterations to the most intensely irradiated area. TEM revealed that although both sets of microstructures appeared strained, the 14 MeV-irradiated damage manifested as milder patches of subcascades and large voids, with no large amorphous clusters classically associated with REBCO fission irradiations, as confirmed by our own fission samples. Computational analysis on the visually indistinguishable respective lattice strains revealed comparable damage metrics of the fusion-like samples to fission samples, despite the much lower total fluences on the former. The nuclear physics origins of these findings and their implications for the superconducting properties are also discussed. These results present an important preliminary step in the rigorous technical readiness qualifications required by this pivotal technology in the burgeoning REBCO-based compact fusion industry. Physical sciences/Materials science/Condensed-matter physics/Superconducting properties and materials Physical sciences/Energy science and technology/Nuclear energy/Nuclear fusion and fission Physical sciences/Mathematics and computing/Computational science Physical sciences/Physics/Nuclear physics/Experimental nuclear physics Full Text Additional Declarations There is NO Competing Interest. 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-8888914","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":599576581,"identity":"34b4a94a-8ae0-44b0-be36-0bd3d645e061","order_by":0,"name":"Christopher 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To expand the current understanding of how the inherently reduced shielding of these proposed designs affects the radiation-sensitive high temperature superconductors, the activation spectra and microstructure of REBCO tapes irradiated more traditionally with fission-reactor neutrons were compared to those irradiated with the higher-fidelity fusion-like spectrum produced by thick target deuteron breakup in a first-of-its-kind irradiation experiment on these coated conductors. For the fusion-like case, several peaks in the activation spectrum confirmed high-threshold nuclear reactions, and SEM revealed superficial alterations to the most intensely irradiated area. TEM revealed that although both sets of microstructures appeared strained, the 14 MeV-irradiated damage manifested as milder patches of subcascades and large voids, with no large amorphous clusters classically associated with REBCO fission irradiations, as confirmed by our own fission samples. Computational analysis on the visually indistinguishable respective lattice strains revealed comparable damage metrics of the fusion-like samples to fission samples, despite the much lower total fluences on the former. The nuclear physics origins of these findings and their implications for the superconducting properties are also discussed. 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