Fabrication and characterization of 3Y-ZrO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> ceramic based on the raw materials dispersed by three-roller mixing
The homogeneous dispersion of the raw materials is the key process to prepare 3Y-ZrO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> ceramics. In engineering, the three-roller mixing is suitable for dispersing the high viscosity slurries containing the fine ceramic powder...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | zho |
| Published: |
Journal of Materials Engineering
2021-03-01
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| Series: | Cailiao gongcheng |
| Subjects: | |
| Online Access: | http://jme.biam.ac.cn/CN/10.11868/j.issn.1001-4381.2020.000347 |
| Summary: | The homogeneous dispersion of the raw materials is the key process to prepare 3Y-ZrO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> ceramics. In engineering, the three-roller mixing is suitable for dispersing the high viscosity slurries containing the fine ceramic powders, which benefited reducing the amount of dispersion medium and drying time. The commercial 3Y-ZrO<sub>2</sub> powder (80 nm) and two kinds of Al<sub>2</sub>O<sub>3</sub> powders (3 μm and 0.3 μm) were used as the starting materials. 3Y-ZrO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> composite ceramics were prepared by three-roller mixing, die pressing, and sintering. The relation of phase compositions, microstructures, and bending strengths of the ceramics was investigated by XRD, SEM, and universal testing machine. The results show that the microscopic aggregation area of Al<sub>2</sub>O<sub>3</sub> grains with the maximum size of 5-10 μm exists in the 3Y-ZrO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> composite ceramics in addition to the normal dispersed phase of Al<sub>2</sub>O<sub>3</sub> and the continuous phase of 3Y-ZrO<sub>2</sub>. The transition from the tetragonal to the monoclinic phase of 3Y-ZrO<sub>2</sub> occurs with the addition of coarse Al<sub>2</sub>O<sub>3</sub> powders. However, the tetragonal phase shifts to the right with no monoclinic phase detected in the samples with fine Al<sub>2</sub>O<sub>3</sub> powders. The proper addition of the two Al<sub>2</sub>O<sub>3</sub> powders is beneficial to achieving the maximum bending strength when the 3Y-ZrO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> ceramics are sintered at 1600 ℃. However, the curve change of the bending strength of the composite ceramics with fine Al<sub>2</sub>O<sub>3</sub> powder is smoother than that of the samples with coarse Al<sub>2</sub>O<sub>3</sub> powder with the increase of Al<sub>2</sub>O<sub>3</sub> volume fraction. |
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| ISSN: | 1001-4381 1001-4381 |