【摘要】 为了改善钛酸钡陶瓷的介电性能,采用溶胶凝胶法,制备了镧、铈掺杂的钛酸钡基介电陶瓷,研究了镧、铈2种稀土氧化物对其介电性能、耐压程度等性能的影响以及与显微结构的关系。实验表明:2种稀土元素对钛酸钡陶瓷的晶粒生长有较大的抑制作用,镧和铈的掺杂量在1.0%(物质的量分数)左右对钛酸钡陶瓷的介电性能有很好的改善作用。但镧离子和铈离子在钛酸钡中的离子取代情况有所不同,因而,改善性能的作用不同。镧掺杂钛酸钡陶瓷性能好于铈掺杂的钛酸钡陶瓷,掺杂物质的量分数为1.0%的镧掺杂钛酸钡陶瓷的相对介电常数大于4000,从室温到125℃温度范围内,介电常数的温度系数小于10%,击穿场强大于7.5kV/mm。更多还原

【Abstract】 In order to improve electric properties of BaTiO₃ ceramics , La and Ce-doped BaTiO₃ ceramics were prepared by sol-gel technique, dielectric permittivity vs. temperature and voltage withstanding were measured, and microstructure of ceramics was analyzed. The result showes that Ce and La can inhibit the grain growth and reduce the size of grain, and the electric properties of BaTiO₃ ceramics can be improved by adding proper amount of La and Ce dopants. But replacement of Ce 3+ and La 3+ for BaTiO₃ is different. Electric properties of La- doped BaTiO₃ ceramics is better than that of Ce-doped. When content of La in BaTiO₃ ceramics is 1.0mol%, relative dielectric constant is more than 4000, change of relative dielectric constant vs. temperature from 20℃ up to 125℃ is less than 10%,and voltage withstanding is larger than 7.5kV/mm.更多还原