Lu2O3-doped ZnO-Bi2O3-based varistor ceramics samples were prepared by a conventional mixed oxide route and sintered at temperatures in the range of 900-1 000°C,and the microstructures of the varistor ceramics sa...Lu2O3-doped ZnO-Bi2O3-based varistor ceramics samples were prepared by a conventional mixed oxide route and sintered at temperatures in the range of 900-1 000°C,and the microstructures of the varistor ceramics samples were characterized by X-ray diffractometry(XRD)and scanning electron microscopy(SEM);at the same time,the electrical properties and V-I characteristics of the varistor ceramics samples were investigated by a DC parameter instrument for varistors.The results show that the ZnO-Bi2O3-based varistor ceramics with 0.3%Lu2O3(molar fraction)sintered at 950°C exhibit comparatively ideal comprehensive electrical properties.The XRD analysis of the samples shows the presence of ZnO,Bi-rich,spinel Zn7Sb2O12 and Lu2O3-based phases.展开更多
Varistor ceramics of ZnO Bi 2O 3 TiO 2 Sb 2O 3 system have been fabricated by introducing pre fabricated ZnO seed grains with different size distributions respectively. The results show that the varistor properties we...Varistor ceramics of ZnO Bi 2O 3 TiO 2 Sb 2O 3 system have been fabricated by introducing pre fabricated ZnO seed grains with different size distributions respectively. The results show that the varistor properties were significantly influenced by the size of introduced seed grains, and introducing larger seed grains is more advantageous to the modification of microstructure and the improvement of varistor properties. The varistor properties were considerably improved with a moderately increased sintering temperature or time, whereas degraded apparently when the sintering temperature or time was excessively increased. Compared with the sintering time, the sintering temperature plays a more critical role in determining the varistor properties. By introducing pre fabricated ZnO seed grains into the original powders, low voltage ZnO varistor ceramics possessing the desired electrical properties have been produced with a sintering temperature of about 1 210 ℃ and a sintering temperature of 2~2.5 h. [展开更多
采用溶胶-凝胶法制备Ba0.2Sr0.8Zr0.18Ti0.82O3(BSZT)的粉体,以传统工艺制备了4ZnO-Bi2O3作为添加物的BSZT陶瓷。研究了不同4ZnO-Bi2O3玻璃添加量(质量分数0~3%)对BSZT陶瓷烧结特性、微观结构以及电学性能的影响。结果表明,添加适量...采用溶胶-凝胶法制备Ba0.2Sr0.8Zr0.18Ti0.82O3(BSZT)的粉体,以传统工艺制备了4ZnO-Bi2O3作为添加物的BSZT陶瓷。研究了不同4ZnO-Bi2O3玻璃添加量(质量分数0~3%)对BSZT陶瓷烧结特性、微观结构以及电学性能的影响。结果表明,添加适量的4ZnO-Bi2O3玻璃相,大幅降低了BSZT陶瓷的烧结温度,使得晶粒较小且均匀,无气孔;能提高陶瓷的击穿场强。添加质量分数1%4ZnO-Bi2O3玻璃相的BSZT陶瓷的最优烧结温度较纯BSZT陶瓷降低了350℃,1 k Hz频率下,其相对介电常数约为334、介电损耗约为0.7%;击穿场强为10.2×103 V/mm。展开更多
基金Project(50902061)supported by the National Natural Science Foundation of ChinaProject(2011-22)supported by the State Key Laboratory of Inorganic Synthesis and Preparative Chemistry of Jilin University,China+3 种基金Project(20100471380)supported by the China Postdoctoral Science FoundationProject(J50102)supported by the Leading Academic Discipline Program of Shanghai Municipal Education Commission,ChinaProject(10KJD430002)supported by the Universities Natural Science Research Program of Jiangsu Province,ChinaProject(2010002)supported by the Jiangsu University Undergraduate Practice-Innovation Training Program,China
文摘Lu2O3-doped ZnO-Bi2O3-based varistor ceramics samples were prepared by a conventional mixed oxide route and sintered at temperatures in the range of 900-1 000°C,and the microstructures of the varistor ceramics samples were characterized by X-ray diffractometry(XRD)and scanning electron microscopy(SEM);at the same time,the electrical properties and V-I characteristics of the varistor ceramics samples were investigated by a DC parameter instrument for varistors.The results show that the ZnO-Bi2O3-based varistor ceramics with 0.3%Lu2O3(molar fraction)sintered at 950°C exhibit comparatively ideal comprehensive electrical properties.The XRD analysis of the samples shows the presence of ZnO,Bi-rich,spinel Zn7Sb2O12 and Lu2O3-based phases.
文摘Varistor ceramics of ZnO Bi 2O 3 TiO 2 Sb 2O 3 system have been fabricated by introducing pre fabricated ZnO seed grains with different size distributions respectively. The results show that the varistor properties were significantly influenced by the size of introduced seed grains, and introducing larger seed grains is more advantageous to the modification of microstructure and the improvement of varistor properties. The varistor properties were considerably improved with a moderately increased sintering temperature or time, whereas degraded apparently when the sintering temperature or time was excessively increased. Compared with the sintering time, the sintering temperature plays a more critical role in determining the varistor properties. By introducing pre fabricated ZnO seed grains into the original powders, low voltage ZnO varistor ceramics possessing the desired electrical properties have been produced with a sintering temperature of about 1 210 ℃ and a sintering temperature of 2~2.5 h. [
文摘采用溶胶-凝胶法制备Ba0.2Sr0.8Zr0.18Ti0.82O3(BSZT)的粉体,以传统工艺制备了4ZnO-Bi2O3作为添加物的BSZT陶瓷。研究了不同4ZnO-Bi2O3玻璃添加量(质量分数0~3%)对BSZT陶瓷烧结特性、微观结构以及电学性能的影响。结果表明,添加适量的4ZnO-Bi2O3玻璃相,大幅降低了BSZT陶瓷的烧结温度,使得晶粒较小且均匀,无气孔;能提高陶瓷的击穿场强。添加质量分数1%4ZnO-Bi2O3玻璃相的BSZT陶瓷的最优烧结温度较纯BSZT陶瓷降低了350℃,1 k Hz频率下,其相对介电常数约为334、介电损耗约为0.7%;击穿场强为10.2×103 V/mm。