Sintering, crystallization and properties of 2(Mg1−xMnx)O·2Al2O3·5SiO2 ceramics
| Autor: | N. A. Rudina, I.Yu. Molina, Elena Sutormina, Lyubov A. Isupova |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
010302 applied physics
Materials science Scanning electron microscope Process Chemistry and Technology Sintering Cordierite 02 engineering and technology engineering.material 021001 nanoscience & nanotechnology 01 natural sciences Surfaces Coatings and Films Electronic Optical and Magnetic Materials law.invention Chemical engineering law Differential thermal analysis 0103 physical sciences Materials Chemistry Ceramics and Composites engineering Melting point Crystallite Crystallization 0210 nano-technology Porosity |
| Zdroj: | Ceramics International. 45:5203-5209 |
| ISSN: | 0272-8842 |
| Popis: | Mn-substituted cordierites, 2(Mg1−xMnx)O·2Al2O3·5SiO2 (x = 0–1), were prepared from natural components (talc, clay, alumina) and MnO2. Sintering behavior, phase transformation, and microstructural features of the samples were investigated using X-ray diffraction (XRD), differential thermal analysis (DTA), dilatometric measurements and scanning electron microscopy (SEM) with energy dispersive analysis (EDS). The results of DTA and XRD analysis indicate that MnO2 is successively reduced to Mn2O3 and MnO in the sintering process. Mn2+ ions incorporate into the crystal structure of α-cordierite substituting Mg2+ ions in octahedral sites and thus increasing the cordierite unit cell volume. Mn promotes the sintering process: the crystallization temperature, melting point, density and open porosity of Mn-substituted cordierites lowered, whereas the shrinkage and medium pore diameter enlarged with an increase in MnO2 content in the mixture of raw materials. Surface enrichment with Mn with the formation of manganese oxide crystallites was found for the samples with high substitution degree. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect