纳米复合材料导热与介电性能仿真

Simulation on Thermal Conduction and Dielectric Properties of Nanocomposites

以纳米复合材料作为研究体系,选取典型的氮化硼(BN)/环氧树脂(EP)复合材料与钛酸钡(BT)/聚偏氟乙烯(PVDF)复合材料,通过有限元方法研究了纳米填料的体积分数、粒径大小和尺寸分布对复合材料导热性能和介电性能的影响,采用均匀场理论计算了复合材料的等效热导率和等效介电常数。结果表明:随着填料体积分数的提高,BN/EP和BT/PVDF的热导率和介电常数均提高;在相同体积分数、尺寸均匀分布的情况下,BN/EP和BT/PVDF的热导率和介电常数随着粒径增大而增大;在相同体积分数、同一粒径的情况下,BN/EP和BT/PVDF的热导率和介电常数随着粒径标准差增大而增大。因此,根据具体需求适当改变填料含量、粒径大小、粒径标准差是改善材料性能的有效方法。

Typical boron nitride(BN)/epoxy resin(EP)nanocomposite and barium titanate(BT)/polyvinylidene fluoride(PVDF)nanocomposite were selected as research system,and the influence of nano-particle volume fraction,particle size,and size distribution on the thermal conductivity and dielectric properties of the nanocomposites was studied by finite element method.The equivalent thermal conductivity and dielectric constant of the nanocomposite was calculated by mean field theory.The results show that with the increase of nano-particle volume fraction,the thermal conductivity and dielectric constant of BN/EP and BT/PVDF increase.Under the same volume fraction and size distribution,the thermal conductivity and dielectric constant of BN/EP and BT/PVDF increase with the increase of particle size.Under the same volume fraction and particle size,and the thermal conductivity and dielectric constant of BN/EP and BT/PVDF increase with the increase of particle size standard deviation.Consequently,it is an effective way to improve the properties of material by changing the filler content,particle size,and size standard deviation appropriately according to the specific needs.