The Effect of Firing Temperatures on Phase Evolution, Microstructure, and Electrical Properties of Ba(Zr0.05Ti0.95)O3 Ceramics Prepared via Combustion Technique

Abstract

In this work, the effects of calcination temperature (900 ºC-1200 ºC for 2 h-6 h) and sintering temperature (1350 ºC-1550 ºC for 2 h) on phase evolution, microstructure and electrical properties of barium zirconate titanate Ba(Zr 0.05 Ti 0.95)O 3 (BZT) ceramics fabricated through the combustion technique were investigated. Glycine was used as fuel to reduce the reaction temperature. It was found that a single perovskite phase of BZT powders was observed from the sample calcined at 925 ºC for 6 h, which was lower than the solid state reaction technique ~275 ºC. The purity phase of an orthorhombic structure was observed in all ceramic samples. The average particle size (190 nm-420 nm) and the average grain size (2.9 μm-41.4 μm) increased with increased firing temperatures. The maximum theoretical density of ~96.8 % was obtained from the sample sintered at 1450 ºC for 2 h. The dielectric constant at room temperature (T r) and the dielectric constant at Curie temperature (T c) increased with increased sintering temperatures up to 1450 ºC and decreased thereafter. The dielectric properties corresponded to the obtained densities. The remnant polarization (P r) of the BZT ceramic (using the coercive electric field of 20 kV/cm) increased with increasing sintering temperature.

Phase evolution and electrical properties of a new system of (1−x)[BNT–BKT–KNN]–xBCTZ lead-free piezoelectric ceramics synthesized by the solid-state combustion technique

“…The powders were combined with glycine in a ratio of 1:2 and then calcined at 750 C for 2 h. [10] To synthesize (Ba 0.90 Ca 0.10 )(Ti 0.85 Zr 0.15 )O 3 (BCTZ) powder, BaCO 3 (99%), Ca(NO 3 ) 2 Á4 (H 2 O) (99%), TiO 2 (99%) and ZrO 2 (99%) were used as raw materials. In the process, the synthesis of the BCTZ powder was similar to that of the BNTÀBKTÀKNN powders but the uncalcined BCTZ was mixed with glycine in a ratio of 1:1.11 and they were calcined at 1050 C for 2 h. [23] The two calcined powders were mixed at various compositions ð0 x 0:1Þ with 3 wt% of PVA and milled again for 12 h. After drying and pulverizing the mixture powders, samples were pressed into disks of 15 mm diameter and 2 mm thickness under 80 MPa pressure. Samples were sintered at 1125 C for 2 h and were used a heating/cooling rate of 5 C/min.…”

Enhanced Energy Storage Properties of BNT–ST–AN Relaxor Ferroelectric Ceramics Fabrication by the Solid‐State Combustion Technique

“…[28,29] During the combustion process, the reaction mechanism relies on the energy released from the fuel, which accelerates the chemical reaction between the raw materials and also helps to reduce the reaction temperature. [28][29][30][31] The combustion reaction uses glycine as a fuel releases its energy (ΔH ¼ À221.78 kcal mol À1 ) at its adiabatic flame temperature which is around 1248 °C. [31] Moreover, during the reaction, a liquid phase is generated which has a higher diffusion coefficient than a solid medium.…”

“…[28][29][30][31] The combustion reaction uses glycine as a fuel releases its energy (ΔH ¼ À221.78 kcal mol À1 ) at its adiabatic flame temperature which is around 1248 °C. [31] Moreover, during the reaction, a liquid phase is generated which has a higher diffusion coefficient than a solid medium. [29][30][31][32] The solid-state combustion technique also has the important characteristics of simplicity, and relatively low cost and it usually results in products with the desired structure and composition.…”

“…[31] Moreover, during the reaction, a liquid phase is generated which has a higher diffusion coefficient than a solid medium. [29][30][31][32] The solid-state combustion technique also has the important characteristics of simplicity, and relatively low cost and it usually results in products with the desired structure and composition. [29][30][31][32] Hence, it is presumed that the synthesis of BNT-ST-AN ceramics by the solid-state combustion technique can decrease the firing temperature and dwell time, which leads to reduced evaporation of Bi þ and Na þ during the firing process and reduced oxygen vacancies, so as to improve the energy storage properties and E b .…”

“…[29][30][31][32] The solid-state combustion technique also has the important characteristics of simplicity, and relatively low cost and it usually results in products with the desired structure and composition. [29][30][31][32] Hence, it is presumed that the synthesis of BNT-ST-AN ceramics by the solid-state combustion technique can decrease the firing temperature and dwell time, which leads to reduced evaporation of Bi þ and Na þ during the firing process and reduced oxygen vacancies, so as to improve the energy storage properties and E b . In this work, we attempted to synthesize BNT-ST-AN ceramics by the solid-state combustion technique and investigated the effects of the firing temperatures on the phase evolution, morphology, dielectric properties, and energy storage properties of BNT-ST-AN ceramics.…”