{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,9]],"date-time":"2026-05-09T19:54:16Z","timestamp":1778356456365,"version":"3.51.4"},"reference-count":33,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2021,3,9]],"date-time":"2021-03-09T00:00:00Z","timestamp":1615248000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/PD\/BD\/128411\/2017"],"award-info":[{"award-number":["SFRH\/PD\/BD\/128411\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>The considerable decrease in temperature and time makes FLASH sintering a more sustainable alternative for materials processing. FLASH also becomes relevant if volatile elements are part of the material to be processed, as in alkali-based piezoelectrics like the promising lead-free K0.5Na0.5NbO3 (KNN). Due to the volatile nature of K and Na, KNN is difficult to process by conventional sintering. Although some studies have been undertaken, much remains to be understood to properly engineer the FLASH sintering process of KNN. In this work, the effect of FLASH temperature, TF, is studied as a function of the particle size and impurity content of KNN powders. Differences are demonstrated: while the particle size and impurity degree markedly influence TF, they do not significantly affect the densification and grain growth processes. The conductivity of KNN FLASH-sintered ceramics and KNN single crystals (SCs) is compared to elucidate the role of particles\u2019 surface conduction. When particles\u2019 surfaces are not present, as in the case of SCs, the FLASH process requires higher temperatures and conductivity values. These results have implications in understanding FLASH sintering towards a more sustainable processing of lead-free piezoelectrics.<\/jats:p>","DOI":"10.3390\/ma14051321","type":"journal-article","created":{"date-parts":[[2021,3,9]],"date-time":"2021-03-09T12:08:01Z","timestamp":1615291681000},"page":"1321","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Particle Characteristics\u2019 Influence on FLASH Sintering of Potassium Sodium Niobate: A Relationship with Conduction Mechanisms"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8531-090X","authenticated-orcid":false,"given":"Ricardo","family":"Serrazina","sequence":"first","affiliation":[{"name":"Department of Materials and Ceramic Engineering, Campus Santiago, CICECO\u2014Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8743-405X","authenticated-orcid":false,"given":"Camila","family":"Ribeiro","sequence":"additional","affiliation":[{"name":"Department of Materials and Ceramic Engineering, Campus Santiago, CICECO\u2014Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Maria Elisabete","family":"Costa","sequence":"additional","affiliation":[{"name":"Department of Materials and Ceramic Engineering, Campus Santiago, CICECO\u2014Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Luis","family":"Pereira","sequence":"additional","affiliation":[{"name":"CENIMAT-I3N, Campus da Caparica, School of Science and Technology, FCT-NOVA, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal"}]},{"given":"Paula M.","family":"Vilarinho","sequence":"additional","affiliation":[{"name":"Department of Materials and Ceramic Engineering, Campus Santiago, CICECO\u2014Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Ana M. O. R.","family":"Senos","sequence":"additional","affiliation":[{"name":"Department of Materials and Ceramic Engineering, Campus Santiago, CICECO\u2014Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"115","DOI":"10.1016\/j.jeurceramsoc.2018.08.048","article-title":"Flash sintering of ceramics","volume":"39","author":"Biesuz","year":"2019","journal-title":"J. Eur. Ceram. Soc."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"3556","DOI":"10.1111\/j.1551-2916.2010.04089.x","article-title":"Flash Sintering of Nanograin Zirconia in <5 s at 850 \u00b0C","volume":"93","author":"Cologna","year":"2010","journal-title":"J. Am. Ceram. 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