摘要
环氧树脂内部原子的“热胀冷缩”行为及固有的低热导率问题,严重制约环氧树脂在干式直流套管绝缘中的应用。为此,本研究向环氧树脂中引入低热膨胀系数的氮化硼晶须,制备了新型氮化硼晶须/环氧(BNw/EP)复合电介质,并对复合电介质的微观结构、热膨胀系数、导热性能、电气性能、热稳定性、力学性能进行测试分析。结果表明:在20~100℃的温度范围内,氮化硼晶须质量分数为10%的复合电介质的热膨胀系数比纯环氧树脂降低了15%,同时热导率提升至0.28 W/(m·K),高于纯环氧树脂33.33%。此外,其介电常数在10^(2)~10^(6) Hz频段内低于5.28,介质损耗因数低于0.02,且体积电阻率为10^(14)Ω·cm,拉伸强度保持在49.5 MPa左右。本研究证明了在环氧树脂基体中填充氮化硼晶须,可以保证复合电介质的绝缘、介电以及力学性能不受破坏的基础上,有效降低材料热膨胀系数,提高导热性能。
The"thermal expansion and contraction"behavior of the internal atoms in epoxy resin and the intrinsic issue of low thermal conductivity seriously restrict the application of epoxy resin in dry-type DC sleeve insulation.To address this,we introduced boron nitride whiskers with low thermal expansion coefficient into epoxy resin to prepare a new boron nitride whisker/epoxy(BNw/EP)composite dielectric,and its microstructure,thermal expansion coefficient,thermal conductivity,electrical properties,thermal stability,and mechanical properties were tested and analyzed.The results show that within the temperature range of 20-100℃,the thermal expansion coefficient of the composite dielectric with 10% mass fraction of boron nitride whisker is reduced by 15% compared to pure epoxy resin,while the thermal conductivity increases to 0.28 W/(m·K),which is 33.33% higher than that of pure epoxy resin.In addition,its dielectric constant is below 5.28 and the dielectric loss is below 0.02 in the frequency range of 10^(2)-10^(6) Hz,the volume resistivity is 10^(14)Ω·cm,and the tensile strength is maintained at about 49.5 MPa.This study proves that on the basis of ensuring the insulation,dielectric and mechanical properties of the composite dielectric be not damaged,filling the epoxy resin matrix with boron nitride whiskers can effectively reduce the thermal expansion coefficient of the material and improve the thermal conductivity.
作者
宋阳
张豪峰
肖微
罗兵
滕富莉
郝予涛
任俊文
composite dielectricSONG Yang;ZHANG Haofeng;XIAO Wei;LUO Bing;TENG Fuli;HAO Yutao;REN Junwen(Liuzhou Bureau of EHV Power Transmission Company,Liuzhou 545006,China;Southern Power Grid Research Institute Co.,Ltd.,Guangzhou 510670,China;College of Electrical Engineering,Sichuan University,Chengdu 610065,China;School of Electrical Engineering,Xi′an Jiaotong University,Xi′an 710049,China)
出处
《绝缘材料》
CAS
北大核心
2024年第8期39-45,共7页
Insulating Materials
基金
国家自然科学基金联合基金资助项目(U23B20132)
四川省重点研发项目(2023YFG0236)
电力设备电气绝缘国家重点实验室开放基金资助项目(EIPE23210)。
关键词
环氧树脂
氮化硼晶须
热膨胀系数
热导率
介电性能
epoxy resin
boron nitride whisker
thermal expansion property
thermal conductivity
dielectric property
