Two-Step Sintering, Microstructure and Electrical Properties of (Ba, Ca)(Ti, Zr)O₃ Lead-Free Ceramics

Abstract:

In this work, the (Ba_1-xCa_x)(Ti_1-yZr_y)O₃ lead-free ceramics were prepared by the two-step sintering method, and effects of Ca and Zr contents on phase structure, densification, microstructure, and electrical properties were investigated. It was found that all samples showed orthorhombic phase. The highest density of 5.84 ± 0.01 g/cm³ was achieved in x = 0.05, y = 0.05 sample. The average grain size, phase transition temperature, dielectric and piezoelectric properties significantly decreased by introducing of the Ca/Zr content. The ceramics with a small amount of Ca and Zr maintain good piezoelectric properties, and a lower dielectric loss. The composition with x = 0.05, y = 0.025 demonstrated optimum electrical properties of d₃₃ ∼211 pC/N, T_C ∼ 119 °C, ε_r ∼ 1788, and tanδ ∼ 0.04.

• Periodical: Applied Mechanics and Materials (Volume 749)
• Pages: 79-83
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.749.79
• Online since: April 2015
• Authors: Pornsuda Bomlai
• Keywords: Electrical Properties, Lead-Free Materials, Two-Step Sintering

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