【摘要】 研究了Ca掺杂钨镁酸铅 (PMW )陶瓷材料的合成、结构、烧结以及介电性能。结果发现 :在Ca2 + 摩尔分数小于 15 %时 ,能形成单相的PCMW钙钛矿相 ,结构由原来的斜方相向立方相转变。用二步合成法制备的样品容易致密烧结 ,气孔率比一步法制备的样品小。Ca的加入降低了材料的介电损耗 ,在频率为 1MHz时 ,介质损耗达到了 10 - 4 。当Ca2 + 摩尔分数大于 10 %时 ,材料的Curie峰宽化显著 ,介电常数温度系数降低更多还原

【Abstract】 Preparation method, crystal structure, sinterability and dielectric properties of Ca_doped lead magnesium tungstate (PMW) ceramics were investigated. The results show that the single phase perovskite structure of PCMW formed when molar fraction of Ca 2+ was less than 15%, and the structure changed from orthorhombic to cubic. Samples prepared by two_step method form higher relative density and lower porosity than those prepared by one_step method. The addition of Ca 2+ can decrease the dielectric loss, the order of which can reach 10 -4 at 1 MHz. As the molar fraction of doped Ca 2+is greater than 10%, the Curie peak is apparently broadened and the temperature coefficient of dielectric constant is decreased.更多还原