A Study on Microstructure for Influence on Operating Voltage of Zinc-Oxide Ceramic Varistor

Two samples of ZnO doped Ba with the chemical composition, 97ZnO-3BaO, have been prepared via oxalate co-precipitation. During precipitation the first sample, A, was stirred by magnetic stirrer while the second sample, B, was stirred via 40KHz ultrasonic wave. The obtained powders were decomposed at 400°C for 3h, then pressed and sintered at 1200°C for 1.5h. Then XRD, SEM and J-E measurements were performed and analysed. The grain sizes of the obtained ceramics were (0.5-2.26) µm and (80-119) nm for samples A and B, respectively. The J-E measurements revealed that the obtained ceramic has voltage switching characteristics, and that the switching voltage could be controlled by the stirring process.

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Study of Large-Scale Aluminium-Doped Zinc Oxide Ceramic Targets Prepared by Slip Casting

Advances in Materials Science and Engineering ◽

10.1155/2016/6410848 ◽

2016 ◽

Vol 2016 ◽

pp. 1-6

Author(s):

Ling-yun Han ◽

Yong-chun Shu

Keyword(s):

Zinc Oxide ◽

Electrical Properties ◽

Grain Growth ◽

Large Scale ◽

Slip Casting ◽

Visible Region ◽

Oxide Ceramic ◽

Maximum Value ◽

Average Transmittance ◽

Ceramic Targets

Aluminium-doped zinc oxide (AZO) ceramic green compacts at a size of 170 × 340 × 17 mm have been prepared by slip casting. An AZO slurry with good fluidity and viscosity was obtained when 1.2 wt% of dispersant was added, which indicates that the slurry prepared with micrometre particles is more suitable for slip casting. The densification and electrical properties of the AZO targets prepared by particles with different sizes were investigated after sintering from 1380 to 1460°C. The results showed that the relative density of the AZO target prepared with 45 nm particles could reach nearly 98% at 1380°C; the resistivity of the AZO target prepared with nanometre particles could be as low as 1.6 × 10−3 Ω·cm at 1400°C; and the average transmittance of the AZO film prepared with nanometre particles could reach a maximum value of 93.73% in the visible region at 250 W. In this study, the correlation between the density, resistivity, and grain growth of AZO ceramic green compacts was studied.

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The sintering behavior, microstructure, and electrical properties of gallium-doped zinc oxide ceramic targets

Journal of the European Ceramic Society ◽

10.1016/j.jeurceramsoc.2014.05.022 ◽

2014 ◽

Vol 34 (15) ◽

pp. 3715-3722 ◽

Cited By ~ 15

Author(s):

Ming-Wei Wu ◽

Pang-Hsin Lai ◽

Chia-Hong Hong ◽

Fang-Cheng Chou

Keyword(s):

Zinc Oxide ◽

Electrical Properties ◽

Sintering Behavior ◽

Oxide Ceramic ◽

Ceramic Targets

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Study of High-Density Zn-Doped Tungsten Trioxide Ceramic Targets

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.779-780.182 ◽

2013 ◽

Vol 779-780 ◽

pp. 182-186 ◽

Cited By ~ 1

Author(s):

Chao Xiao ◽

Zhong Jian Zhang ◽

Qing Qing Gao ◽

Cun Qi Liu ◽

Fu Liang Shang ◽

...

Keyword(s):

Zinc Oxide ◽

Relative Density ◽

Tungsten Oxide ◽

Vickers Hardness ◽

Tungsten Trioxide ◽

Bending Strength ◽

Oxide Ceramic ◽

Sintering Conditions ◽

Ceramic Targets ◽

Effect Of The Composition

This paper deals with the preparation of zinc oxide doped tungsten oxide target by sintering in oxygenated flow atmosphere. The effect of the composition and the sintering conditions on the properties and microstructures of the targets has been studied. The optimal sintering conditions were found. The sintered zinc doped tungsten oxide ceramic target can achieve a relative density of 99.58%, a bending strength of 31.79MPa and a Vickers hardness of 349MPa.

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