Effects of Calcium Oxide and Magnesium Oxide Stabilizing Agents on the Critical Transformation Size of Tetragonal Zirconia
| Autor: | Zhi Long Zhao, Liang Zhao, Shuang Yao, Yong Qiang Li, Qun Hu Xue |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
010302 applied physics
Materials science Magnesium Mechanical Engineering chemistry.chemical_element 02 engineering and technology 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences chemistry.chemical_compound Transformation (genetics) chemistry Chemical engineering Mechanics of Materials 0103 physical sciences General Materials Science 0210 nano-technology Stabilizing Agents Calcium oxide Tetragonal zirconia Sol-gel |
| Zdroj: | Materials Science Forum. 980:15-24 |
| ISSN: | 1662-9752 |
| DOI: | 10.4028/www.scientific.net/msf.980.15 |
| Popis: | The preparation of tetragonal zirconia nanopowders by sol–gel method using zirconium oxychloride as raw material, ammonia water and sodium hydroxide solution as precipitant, and calcium oxide or magnesium oxide powders as stabilizing agents is described. After suction filtration, drying, and calcination, tetragonal zirconia nanopowders with different particle size and tetragonal phase content were obtained. The particle size and phase composition of the powders are characterized by using a laser particle size analyzer and an X-ray diffractometer, and the tetragonal phase content and grain size are calculated from the crystal plane formula and Scherrer formula. The analysis of the relationship between the tetragonal phase content and the particle size of the zirconia nanopowders stabilized by calcium oxide and magnesium oxide at room temperature reveals the inhibitory effect of the stabilizing agents on the growth of zirconia grains. The stabilized zirconia nanopowder is finer than unstabilized zirconia nanopowder, and the particle distribution is more uniform in the former. The stabilizing effect of calcium oxide is superior to that of magnesium oxide; the critical transformation size of the zirconia grains stabilized by calcium oxide is the largest, and that of unstabilized zirconia is the smallest. The critical transformation size of calcium oxide-stabilized, magnesium oxide-stabilized, and unstabilized zirconia nanopowders is 18–22.6 nm, 24–28 nm, and 26–33.6 nm, respectively. Under the same calcination condition, the calcium oxide-stabilized zirconia nanopowder retains the highest tetragonal phase content at room temperature. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|