Effect of activating additives on the cold sintering process of (MnFeCoNiCu)<sub>3</sub>O<sub>4</sub> high-entropy ceramics
Objectives. To obtain experimental data on the effect of activating additive type on the cold sintering process of (MnFeCoNiCu)3O4 high-entropy ceramic. The following substances were used as activating additives: ammonium acetate (CH3COONH4), acetic acid (CH3COOH), ammonium chloride (NH4Cl), potassi...
| Main Authors: | , , , , , , |
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| Format: | Article |
| Language: | Russian |
| Published: |
MIREA - Russian Technological University
2022-11-01
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| Series: | Тонкие химические технологии |
| Subjects: | |
| Online Access: | https://www.finechem-mirea.ru/jour/article/view/1884 |
| Summary: | Objectives. To obtain experimental data on the effect of activating additive type on the cold sintering process of (MnFeCoNiCu)3O4 high-entropy ceramic. The following substances were used as activating additives: ammonium acetate (CH3COONH4), acetic acid (CH3COOH), ammonium chloride (NH4Cl), potassium fluoride dihydrate (КF·2H2O), lithium fluoride (LiF), sodium fluoride (NaF), and sodium hydroxide (NaOH).Methods. Synthesis of the initial powder by low-temperature self-propagating method; investigation of the powder particles size distribution by laser diffraction method; analysis of the particle shape and compacted sample microstructure by scanning electron microscopy; investigation of the phase composition by X-ray phase analysis; high-entropy ceramic sample consolidation by cold sintering process. The density of the initial powder and the relative density of cold sintered samples were determined by the Archimedes method.Results. Samples with a relative density of over 0.70 were obtained using distilled water, CH3COONH4 and NaOH during cold sintering at 300 °C, with a holding time of 30 min and pressure 315 MPa.Conclusions. For the first time, the effect of the type of activating additive on the relative density of high-entropy ceramics (MnFeCoNiCu)3O4 samples obtained by cold sintering process has been experimentally demonstrated. The samples microstructures have pronounced differences: 20 wt % distilled water does not lead to grain growth, with only their compaction to 0.71 relative density observed; however, the addition of 0.1 wt % CH3COONH4 and NaOH increases the average grain size when reaching similar relative densities (0.70 and 0.71, respectively). X-ray diffraction analysis showed that the cold sintering process does not lead to a change in the phase composition of the initial (MnFeCoNiCu)3O4 powder, confirming the preservation of the high-entropy structure. |
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| ISSN: | 2410-6593 2686-7575 |