【摘要】 用传统氧化物合成法于950℃低温烧结制备出掺杂二价离子的PNN基弛豫铁电陶瓷,研究了二价离子(Mg2+、Ca2+、Sr2+和Ba2+)掺杂对PNN基陶瓷结构和性能的影响。结果表明:掺杂不同的二价离子会有不同的焦绿石相出现,掺杂Mg2+对PNN基陶瓷的介电性能影响不大;而掺杂Ca2+、Sr2+和Ba2+可促进PNN基陶瓷收缩致密化,有效提高PNN基陶瓷的介电温度稳定性,使居里温度向低温方向移动。在几种二价离子中,掺加Sr2+后的PNN基陶瓷不仅显微组织最致密,而且具有较大的绝缘电阻率和优异的温度稳定性。更多还原

【Abstract】 The PNN-based ceramics were prepared and the effect of doped Mg²⁺, Ca²⁺, Sr²⁺ and Ba²⁺ on phase structure and dielectric properties of PNN-based ceramics was investigated. The results show that different pyrochlore phase appeared in the doped ceramics, which should be attributed to replacing Pb²⁺ by bivalent ions. The Curie temperature can be shifted to lower temperature and the temperature stability can be improved after bivalent ions were doped in the PNN-based ceramics. The sample of Sr²⁺ doped ceramics has the biggest density and insulation resistivity, as well as excellent temperature stability of dielectric properties.更多还原