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Two types of starting powders were used to synthesis AlON powder via the carbothermal reduction and nitridation (CRN) route, the Al2O3 and C mixture, and the Al2O3/C core–shell. Al2O3/C core–shell resulted in lower carbon content and lower synthesis temperature for CRN method. AlON powder was synthesized using Al2O3 and C then was sintered via SPS at 1500, 1600, and 1700°C for 10‐30 min in a vacuum atmosphere. A sample with the highest transmittance was annealed at 1250°C for 2, 4, and 8 h in air. The characteristics of AlON powder and bulk samples were investigated by XRD, DLS, FT‐IR, elemental analysis of carbon and sulfur, SEM, EDS, and UV–Vis spectroscopy analyses. The annealing process for 2 h improved the transmittance from 31% to 58% at the wavelength of 600 nm. AlON powder synthesized using Al2O3/C core–shell, was SPSed at 1700°C for 15 min and annealed at 1250°C for 2 h was used to make a sample of 1.7 mm thickness whose transmittance was found to be 81%. [ABSTRACT FROM AUTHOR]

Lead zirconate titanate (PZT95/5) based piezoelectric ceramics with the compositions Pb0.99(Zr0.95Ti0.05)0.98Ta0.02O3 (PZTT) and Pb0.99−0.5x(Zr0.95Ti0.05)0.98−xNb0.02TaxO3 (PZTN), where x = 0.0, 0.005, 0.010, 0.015 and 0.020 were synthesized using conventional solid state sintering at 1250 °C for 2 h in air. The effect of tantalum substitution on the microstructure, dielectric and piezoelectric properties of the samples were studied. The results showed that the Ta-doped samples had finer microstructures. The PZTT samples had microstructures with finer grains (average grain size of 3.80 µm) in comparison with the PZTN samples (average grain size of 5.33 µm). The relative densities of the PZTN and PZTT samples were approximately 94.1 and 94.4%, respectively. Moreover, the relative dielectric constant (εr), piezoelectric coefficient (d31) and elastic compliance (S11E) of the samples reached the maximum values of 349, − 15.2 PC/N and 8.42 Pm2/N, respectively at 1.5 mol% tantalum substitution. Furthermore, the relative dielectric constant (εr), piezoelectric coefficient (d33) and voltage coefficient (g33) of the PZTN samples reached the optimal values of 306, 69 PC/N and 25.44 mV m/N, respectively, in comparison with the PZTT samples (329, 67 PC/N and 21.43 mV m/N, respectively). The results indicate that the tantalum doped PZT95/5 ceramics can be used for pulsed power devices. [ABSTRACT FROM AUTHOR]