Influence of dysprosium oxide doping on thermophysical properties of LaMgAl11O19 ceramics

✍ Scribed by Yuan-Hong Wang; Jia-Hu Ouyang; Zhan-Guo Liu

• Publisher: Elsevier Science
• Year: 2010
• Weight: 468 KB
• Volume: 31
• Category: Article
• ISSN: 0261-3069
• DOI: 10.1016/j.matdes.2010.01.058

✦ Synopsis

This paper deals with the influence of dysprosium oxide doping on thermophysical properties of LaM-gAl 11 O 19 ceramics. LaMgAl 11 O 19 ceramic powders doped with different contents of dysprosium oxide were pressureless-sintered at 1700 °C for 10 h in air to fabricate dense bulk ceramics. La 1Àx Dy x MgAl 11 O 19 (x = 0, 0.1, 0.2, 0.3) ceramics have a relative density of 90.7-96.0%, and exhibit a single phase of magnetoplumbite structure. Thermal diffusivity and thermal expansion coefficients of La 1Àx Dy x MgAl 11 O 19 ceramics were measured with a laser flash method and a high-temperature dilatometer. Thermal diffusivity of La 1Àx Dy x MgAl 11 O 19 ceramics decreases with increasing Dy 2 O 3 content at identical temperature levels. The measured thermal conductivity of La 1Àx Dy x MgAl 11 O 19 ceramics is located in the range of 2.52-2.89 W m À1 K À1 at 1200 °C. Thermal expansion coefficient of La 0.8 Dy 0.2 MgAl 11 O 19 ceramic is slightly higher than that of undoped LaMgAl 11 O 19 ceramic at identical temperature levels.