{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T01:52:12Z","timestamp":1760233932236,"version":"build-2065373602"},"reference-count":26,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2021,3,5]],"date-time":"2021-03-05T00:00:00Z","timestamp":1614902400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Engineering and Physical Sciences Research Council UK","award":["EP\/N026136\/1"],"award-info":[{"award-number":["EP\/N026136\/1"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Ductile-to-brittle-transition refers to observable change in fracture mode with decreasing temperature\u2014from slow ductile crack growth to rapid cleavage. It is exhibited by body-centred cubic metals and presents a challenge for integrity assessment of structural components made of such metals. Local approaches to cleavage fracture, based on Weibull stress as a cleavage crack-driving force, have been shown to predict fracture toughness at very low temperatures. However, they are ineffective in the transition regime without the recalibration of Weibull stress parameters, which requires further testing and thus diminishes their predictive capability. We propose new Weibull stress formulation with thinning function based on obstacle hardening model, which modifies the number of cleavage-initiating features with temperature. Our model is implemented as a post-processor of finite element analysis results. It is applied to analyses of standard compact tension specimens of typical reactor pressure vessel steel, for which deformation and fracture toughness properties in the transition regime are available. It is shown that the new Weibull stress is independent of temperature, and of Weibull shape parameter, within the experimental error. It accurately predicts the fracture toughness at any temperature in the transition regime without relying upon empirical fits for the first time.<\/jats:p>","DOI":"10.3390\/ma14051224","type":"journal-article","created":{"date-parts":[[2021,3,5]],"date-time":"2021-03-05T05:03:15Z","timestamp":1614920595000},"page":"1224","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Incorporation of Obstacle Hardening into Local Approach to Cleavage Fracture to Predict Temperature Effects in the Ductile to Brittle Transition Regime"],"prefix":"10.3390","volume":"14","author":[{"given":"Maria S.","family":"Yankova","sequence":"first","affiliation":[{"name":"Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, Oxford Rd, Manchester M13 9PL, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3454-7341","authenticated-orcid":false,"given":"Andrey P.","family":"Jivkov","sequence":"additional","affiliation":[{"name":"Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, Oxford Rd, Manchester M13 9PL, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rajesh","family":"Patel","sequence":"additional","affiliation":[{"name":"National Nuclear Laboratory, Sperry Way, Stonehouse, GL10 3UT, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"511","DOI":"10.1179\/msc.1978.12.11.511","article-title":"Effects of microstructure on cleavage fracture stress in steel","volume":"12","author":"Curry","year":"1978","journal-title":"Met. 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