Effect of milling on the anisotropic grain growth in a sintered Ba5Nb4O15 specimen and its effect on microwave dielectric properties
Journal
International Journal of Applied Ceramic Technology
Journal Volume
16
Journal Issue
5
Pages
2094-2100
Date Issued
2019
Author(s)
Abstract
Abstract In this study, relationships between the processing, microstructure, and properties of barium niobate (Ba 5 Nb 4 O 15 ) are investigated. The milling of a Ba 5 Nb 4 O 15 powder in water is effective with respect to size reduction. However, after milling in water, BaCO 3 is formed within the slurry. With the increase in the amount of BaCO 3 formed, the aspect ratio of the elongated Ba 5 Nb 4 O 15 grains increases. The formation of the elongated Ba 5 Nb 4 O 15 grains prohibits the densification. Hence, the microwave dielectric properties, including permittivity and quality factor, are poor because of the low density. In addition, milling in ethanol is carried out for comparison: A lower amount of BaCO 3 is formed after milling in ethanol; the extent of anisotropic grain growth is thus reduced.
SDGs
Type
journal article