Effect of Dispersant Content on Nanograined BME MLCC Powder Prepared by Aqueous Chemical Coating Method

Abstract:

Dispersion plays an important role in aqueous chemical coating process for the preparation of BaTiO3 based next generation BME MLCC powder, since it affects coating coverage and layer morphology of the BaTiO3 particles as well as the microstructure and dielectric properties of the ceramics. In this paper, Poly (acrylic acid-co-maleic acid) (PAM) is used as dispersant, its content influences are carefully investigated. It is known that low content of dispersant leads to not only poor dispersion, low coverage and irregular coating layer of BaTiO3 particles, but also bad temperature coefficient of capacitances and inhomogeneous microstructure of the resultant BaTiO3 ceramics, while excessive dispersant deteriorates the microstructure and performance by reducing the density of ceramic. With proper dispersant content, the particles are dispersed and coated perfectly, finally the dense X7R-satisfied ceramic are obtained with average grain size 103nm and fine microstructure, meeting the requirement of next generation MLCCs.

• Periodical: Key Engineering Materials (Volumes 512-515)
• Pages: 153-157
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.512-515.153
• Online since: June 2012
• Authors: Yi Chi Zhang, Xiao Hui Wang, Jin Yong Kim, Long Tu Li
• Keywords: Aqueous Chemical Coating, Dielectric Materials, Dispersant Content, X7R

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