Particle Characteristics’ Influence on FLASH Sintering of Potassium Sodium Niobate: A Relationship with Conduction Mechanisms
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 K<sub>0.5&l...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2021-03-01
|
| Series: | Materials |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1996-1944/14/5/1321 |
| _version_ | 1797541969190191104 |
|---|---|
| author | Ricardo Serrazina Camila Ribeiro Maria Elisabete Costa Luis Pereira Paula M. Vilarinho Ana M. O. R. Senos |
| author_facet | Ricardo Serrazina Camila Ribeiro Maria Elisabete Costa Luis Pereira Paula M. Vilarinho Ana M. O. R. Senos |
| author_sort | Ricardo Serrazina |
| collection | DOAJ |
| description | 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 K<sub>0.5</sub>Na<sub>0.5</sub>NbO<sub>3</sub> (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, T<sub>F</sub>, 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 T<sub>F</sub>, 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’ surface conduction. When particles’ 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. |
| first_indexed | 2024-03-10T13:24:05Z |
| format | Article |
| id | doaj.art-5180fa7fa656493585b5821c70fc7664 |
| institution | Directory Open Access Journal |
| issn | 1996-1944 |
| language | English |
| last_indexed | 2024-03-10T13:24:05Z |
| publishDate | 2021-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Materials |
| spelling | doaj.art-5180fa7fa656493585b5821c70fc76642023-11-21T09:48:39ZengMDPI AGMaterials1996-19442021-03-01145132110.3390/ma14051321Particle Characteristics’ Influence on FLASH Sintering of Potassium Sodium Niobate: A Relationship with Conduction MechanismsRicardo Serrazina0Camila Ribeiro1Maria Elisabete Costa2Luis Pereira3Paula M. Vilarinho4Ana M. O. R. Senos5Department of Materials and Ceramic Engineering, Campus Santiago, CICECO—Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, PortugalDepartment of Materials and Ceramic Engineering, Campus Santiago, CICECO—Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, PortugalDepartment of Materials and Ceramic Engineering, Campus Santiago, CICECO—Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, PortugalCENIMAT-I3N, Campus da Caparica, School of Science and Technology, FCT-NOVA, Universidade NOVA de Lisboa, 2829-516 Caparica, PortugalDepartment of Materials and Ceramic Engineering, Campus Santiago, CICECO—Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, PortugalDepartment of Materials and Ceramic Engineering, Campus Santiago, CICECO—Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, PortugalThe 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 K<sub>0.5</sub>Na<sub>0.5</sub>NbO<sub>3</sub> (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, T<sub>F</sub>, 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 T<sub>F</sub>, 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’ surface conduction. When particles’ 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.https://www.mdpi.com/1996-1944/14/5/1321FLASH sinteringK<sub>0.5</sub>Na<sub>0.5</sub>NbO<sub>3</sub>KNNFLASH temperatureparticle sizeimpurities |
| spellingShingle | Ricardo Serrazina Camila Ribeiro Maria Elisabete Costa Luis Pereira Paula M. Vilarinho Ana M. O. R. Senos Particle Characteristics’ Influence on FLASH Sintering of Potassium Sodium Niobate: A Relationship with Conduction Mechanisms Materials FLASH sintering K<sub>0.5</sub>Na<sub>0.5</sub>NbO<sub>3</sub> KNN FLASH temperature particle size impurities |
| title | Particle Characteristics’ Influence on FLASH Sintering of Potassium Sodium Niobate: A Relationship with Conduction Mechanisms |
| title_full | Particle Characteristics’ Influence on FLASH Sintering of Potassium Sodium Niobate: A Relationship with Conduction Mechanisms |
| title_fullStr | Particle Characteristics’ Influence on FLASH Sintering of Potassium Sodium Niobate: A Relationship with Conduction Mechanisms |
| title_full_unstemmed | Particle Characteristics’ Influence on FLASH Sintering of Potassium Sodium Niobate: A Relationship with Conduction Mechanisms |
| title_short | Particle Characteristics’ Influence on FLASH Sintering of Potassium Sodium Niobate: A Relationship with Conduction Mechanisms |
| title_sort | particle characteristics influence on flash sintering of potassium sodium niobate a relationship with conduction mechanisms |
| topic | FLASH sintering K<sub>0.5</sub>Na<sub>0.5</sub>NbO<sub>3</sub> KNN FLASH temperature particle size impurities |
| url | https://www.mdpi.com/1996-1944/14/5/1321 |
| work_keys_str_mv | AT ricardoserrazina particlecharacteristicsinfluenceonflashsinteringofpotassiumsodiumniobatearelationshipwithconductionmechanisms AT camilaribeiro particlecharacteristicsinfluenceonflashsinteringofpotassiumsodiumniobatearelationshipwithconductionmechanisms AT mariaelisabetecosta particlecharacteristicsinfluenceonflashsinteringofpotassiumsodiumniobatearelationshipwithconductionmechanisms AT luispereira particlecharacteristicsinfluenceonflashsinteringofpotassiumsodiumniobatearelationshipwithconductionmechanisms AT paulamvilarinho particlecharacteristicsinfluenceonflashsinteringofpotassiumsodiumniobatearelationshipwithconductionmechanisms AT anamorsenos particlecharacteristicsinfluenceonflashsinteringofpotassiumsodiumniobatearelationshipwithconductionmechanisms |