Dielectric properties of nano-(MgO–Gd2O3) Co-doped alumina for high voltage insulators. Issue 18 (15th December 2020)

• Record Type: Journal Article
• Authors: Naga, S.M.; El-Mehalawy, N.; Awaad, M.; Eliyan, T.
• Is Part Of: Ceramics international. Volume 46:Issue 18(2020)Part A
• Page Start: 28390
• Page End: 28399
• Publication Date: 2020-12-15
• Subjects: Dielectric ceramics -- Rare-earth elements -- Dielectric properties -- Physico-mechanical properties; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2020.07.343
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: The effect of doping with nano-MgO and co-doping with nano-MgO–Gd2 O3 on the densification behavior, mechanical properties, and dielectric behavior of alumina was evaluated. Magnesium oxide-doped alumina nanoparticles were prepared by the sol-gel method with varying nano-MgO ratios (5, 6, and 7 mass %). Alumina samples containing 7 mass % MgO showed the highest densification and exhibited the greatest mechanical strength due to reduced porosity (3.22 % for 1750 ° C). The doping of alumina with nano-MgO also improved the breakdown voltage and resistivity. Co-doping of alumina also enhanced the densification and mechanical properties of sintered samples. The sample co-doped with a low content of nano-MgO–Gd2 O3 (7 and 1 mass %, respectively) and sintered at 1750 ° C for 1 h displayed the best properties among the studied samples. They exhibited the best electrical properties, with the highest breakdown voltage and resistivity, and the lowest permittivity and dielectric loss.