Study On Preparation And Properties Of Epoxy Resin/BN Ordered Composite Through Magnetic Alignment

Epoxy resin composites have excellent electrical and thermal properties and are widely used in power transmission projects.How to improve the flashover voltage and thermal conductivity of composites is an important research content in the field of high voltage insulation.At present,the influence of magnetic modification of fillers on the surface flashover characteristics and thermal conductivity of epoxy resin composites is not clear.Therefore,this paper conducts an in-depth study of this issue.Firstly,boron nitride（BN）was selected as filler and its magnetic modification was carried out.The improved wet chemical coprecipitation method was used to deposit Fe₃O₄ nanoparticles on the surface of BN to make BN magnetically responsive.The epoxy resin/BN composite material was prepared by BN or magnetically modified BN respectively,wherein the modified BN was rotated and oriented along the magnetic field line by magnetization treatment to obtain an epoxy resin/BN ordered composite material.Secondly,The flashover and charge dissipation rate of BN/epoxy resin and magnetically modified BN/epoxy resin composites were studied by DC flashover experiment platform and surface charge dissipation measurement system.The effects of magnetic modification of the filler and the material magnetization treatment on the flashover voltage and surface charge dissipation rate were analyzed.Finally,the sample of materials were prepared according to the measurement standard.The thermal conductivity of the epoxy resin composites under the disordered and ordered state was measured by laser pulse method.The influence of filler filling amount and order degree on the thermal conductivity of the materials was analyzed.The results of the paper show that epoxy resin/BN ordered composites can improve the flashover voltage level in a short time.And the directional thermal network chain formed by EP/BN ordered composites can improve the thermal diffusivity of the composites,thereby enhancing the thermal conductivity of the composites.