High-strength microporous corundum-mullite refractory aggregates with sub-micron pores using vacuum impregnation treatment
A novel route was proposed to decrease the pore size and enhance the strength of microporous corundum-mullite refractory aggregates, which were fabricated by using the vacuum impregnation treatment of porous Al2O3 powder with silica sol. The effect of the SiO2 content (0–23.6 wt. %) on the phase com...
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| Format: | Article |
| Language: | English |
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Elsevier
2022-07-01
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| Series: | Journal of Materials Research and Technology |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2238785422009528 |
| _version_ | 1811188812583272448 |
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| author | Zhe Chen Wen Yan Stefan Schafföner Jinna Zhi Nan Li |
| author_facet | Zhe Chen Wen Yan Stefan Schafföner Jinna Zhi Nan Li |
| author_sort | Zhe Chen |
| collection | DOAJ |
| description | A novel route was proposed to decrease the pore size and enhance the strength of microporous corundum-mullite refractory aggregates, which were fabricated by using the vacuum impregnation treatment of porous Al2O3 powder with silica sol. The effect of the SiO2 content (0–23.6 wt. %) on the phase composition, microstructures and physical properties of the refractory aggregates was studied. It was found that the sub-micron pore structure inside the pseudomorph particles was effectively preserved due to the volume expansion effect of mullite and the mullite sintering neck formation between the α-Al2O3 microcrystallites. With the SiO2 content increasing from 0 to 13.0 wt. %, the pseudomorph particles containing a large number of sub-micron pores formed in the refractory aggregates resulting from the introduction of silica sol. This resulted in the decrease of intra-particle pore size as well as the development of mullite sintering necks between the pseudomorph particles. The strength of the refractory aggregates was therefore enhanced. With a further increase of SiO2 content to 16.4 and 23.6 wt. %, the inter-particle pore sizes increased due to the mullite volume expansion between the pseudomorph particles, which was responsible for the decrease of strength. Overall, the optimized product is the microporous corundum-mullite refractory aggregates with the addition of 13.0 wt. % SiO2, which showed an apparent porosity of 45.4% and a high compressive strength of 56.4 MPa. Significantly, it also had a median pore size of only 1.24 μm and contained a large number of sub-micron pores. |
| first_indexed | 2024-04-11T14:24:29Z |
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| institution | Directory Open Access Journal |
| issn | 2238-7854 |
| language | English |
| last_indexed | 2024-04-11T14:24:29Z |
| publishDate | 2022-07-01 |
| publisher | Elsevier |
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| series | Journal of Materials Research and Technology |
| spelling | doaj.art-6fb36fbf3df44f37976a3bccf30002f02022-12-22T04:18:55ZengElsevierJournal of Materials Research and Technology2238-78542022-07-011934333442High-strength microporous corundum-mullite refractory aggregates with sub-micron pores using vacuum impregnation treatmentZhe Chen0Wen Yan1Stefan Schafföner2Jinna Zhi3Nan Li4The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan, 430081, China; CNRS, CEMHTI UPR3079, 1D, Avenue de La Recherche Scientifique CS90055, Orléans Cedex 2, 45071, FranceThe State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan, 430081, China; Corresponding author.Ceramic Materials Engineering, University of Bayreuth, Bayreuth, 95447, GermanyThe State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan, 430081, ChinaThe State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan, 430081, ChinaA novel route was proposed to decrease the pore size and enhance the strength of microporous corundum-mullite refractory aggregates, which were fabricated by using the vacuum impregnation treatment of porous Al2O3 powder with silica sol. The effect of the SiO2 content (0–23.6 wt. %) on the phase composition, microstructures and physical properties of the refractory aggregates was studied. It was found that the sub-micron pore structure inside the pseudomorph particles was effectively preserved due to the volume expansion effect of mullite and the mullite sintering neck formation between the α-Al2O3 microcrystallites. With the SiO2 content increasing from 0 to 13.0 wt. %, the pseudomorph particles containing a large number of sub-micron pores formed in the refractory aggregates resulting from the introduction of silica sol. This resulted in the decrease of intra-particle pore size as well as the development of mullite sintering necks between the pseudomorph particles. The strength of the refractory aggregates was therefore enhanced. With a further increase of SiO2 content to 16.4 and 23.6 wt. %, the inter-particle pore sizes increased due to the mullite volume expansion between the pseudomorph particles, which was responsible for the decrease of strength. Overall, the optimized product is the microporous corundum-mullite refractory aggregates with the addition of 13.0 wt. % SiO2, which showed an apparent porosity of 45.4% and a high compressive strength of 56.4 MPa. Significantly, it also had a median pore size of only 1.24 μm and contained a large number of sub-micron pores.http://www.sciencedirect.com/science/article/pii/S2238785422009528Microporous corundum-mullite aggregatesVacuum impregnation treatmentMicrostructuresSub-micron poresStrength |
| spellingShingle | Zhe Chen Wen Yan Stefan Schafföner Jinna Zhi Nan Li High-strength microporous corundum-mullite refractory aggregates with sub-micron pores using vacuum impregnation treatment Journal of Materials Research and Technology Microporous corundum-mullite aggregates Vacuum impregnation treatment Microstructures Sub-micron pores Strength |
| title | High-strength microporous corundum-mullite refractory aggregates with sub-micron pores using vacuum impregnation treatment |
| title_full | High-strength microporous corundum-mullite refractory aggregates with sub-micron pores using vacuum impregnation treatment |
| title_fullStr | High-strength microporous corundum-mullite refractory aggregates with sub-micron pores using vacuum impregnation treatment |
| title_full_unstemmed | High-strength microporous corundum-mullite refractory aggregates with sub-micron pores using vacuum impregnation treatment |
| title_short | High-strength microporous corundum-mullite refractory aggregates with sub-micron pores using vacuum impregnation treatment |
| title_sort | high strength microporous corundum mullite refractory aggregates with sub micron pores using vacuum impregnation treatment |
| topic | Microporous corundum-mullite aggregates Vacuum impregnation treatment Microstructures Sub-micron pores Strength |
| url | http://www.sciencedirect.com/science/article/pii/S2238785422009528 |
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