高介电CaCu_3Ti_4O_(12)填充相对电力绝缘材料介电性能的影响

On Effect of Dielectric Properties of Electric Power Insulation Material with High Dielectric CaCu_3Ti_4O_(12) Filler

通过溶胶凝胶-自蔓延法制备微米CCTO陶瓷填料,并以LDPE为基体,并采用熔融共混-热压成型工艺制备LDPE-CCTO复合介质,利用介电频谱测试仪分析其介电性能,研究不同质量分数CCTO填料对LDPE介质的介电常数、介质损耗和交流电导率特性的影响。研究表明,CCTO填料能够增强LDPE介质的介电参数。较LDPE介电常数1.8相比,20wt%CCTO填充的LDPE-CCTO复合介质介电常数约为2.6,其增强效果为43%,并且仍具有良好的绝缘性能和电场分散性。LDPE-CCTO复合介质的低频介电常数增加很可能源于CCTO陶瓷的本征巨介电特性。

Micrometer CCTO ceramic fil lers were prepared by sol-gel auto-combustion method and LDPE-CCTO composite dielectrics with LDPE as matrix were prepared by the technology of melt-mixing and hot compression molding. Then, the dielectric properties of LDPE-CCTO were analyzed by dielectric spectrum analyzer. Finally, the effects of CCTO fillers with different mass fraction on the dielectric constant, dielectric loss and ac conductivity of LDPE dielectric were studied. The results showed that CCTO filler could enhance dielectric parameters of LDPE dielectric. Compared with the dielectric constant of LDPE, approximately equal to 1.8, the dielectric constant of LDPE-CCTO composite dielectric filled with 20wt% CCTO was about 2.6, enhancing 43% and keeping the good insulation and electric field dispersion. And, the increase of the low frequency dielectric constant of LDPE-CCTO composite dielectric was probably due to the original giant dielectric property of CCTO.