Dielectric strength and energy storage density in Ba_6−3xLa_8+2xTi₁₈O₅₄ (x = 0.5, 2/3, and 0.75) ceramics were investigated as functions of composition and microstructure. With increasing x, although the dielectric constant decreased from 113 to 102, the energy storage density increased from 2.3 J/cm³ to 3.2 J/cm³ due to the increased dielectric strength for ceramics prepared by conventional sintering. The energy storage was further improved to 4.2 J/cm³ in ceramics prepared by spark plasma sintering under an electric field of 1058 kV/cm. Both dielectric strength and energy storage density in the present ceramics indicated the strong processing and microstructure dependence. The optimum dielectric strength and energy storage density were achieved in the dense ceramics with fine grains, while both dielectric strength and energy storage density decreased in the ceramics with coarse columnar grains.

中文翻译：

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提高Ba6−3xLa8 + 2xTi18O54（x = 0.5、2 / 3和0.75）陶瓷的介电强度和能量存储密度

研究了Ba _{6−3 x} La _{8 + 2 x} Ti ₁₈ O ₅₄（x  = 0.5、2 / 3和0.75）陶瓷的介电强度和储能密度，作为成分和微观结构的函数。随着x的增加，尽管介电常数从113减小到102，但是由于通过常规烧结制备的陶瓷的介电强度增加，能量存储密度从2.3J / cm ³增加到3.2J / cm ³。能量存储进一步提高到4.2 J / cm ³在1058 kV / cm的电场下通过火花等离子体烧结制得的陶瓷中的陶瓷。本陶瓷中的介电强度和能量存储密度都表明了强烈的加工和微观结构依赖性。在具有细晶粒的致密陶瓷中，获得了最佳的介电强度和储能密度，而在具有粗柱状晶粒的陶瓷中，介电强度和储能密度均下降。