| Due to the excellent self-cleaning property,the superhydrophobic coating owns potential application prospects in enhancing the surface electrical performance of the electrical power facility.However,several problems such as random distribution of the vulnerable micro-structure,and the unclear critical condition of the electric-field-driven motion of the droplet impede the development and application of the superhydrophobic coating.Based on the capillary induced microstructure shaping effect,a preparation method of durable Si C/fluorocarbon resin superhydrophobic coating was proposed.The distortion of the surface electric field of the coating was relived via the nonlinear electrical conductivity and electrical trap distribution.Combined with the superhydrophobicity and the electric-field-driven motion of the water droplets,the surface flashover performance and the electroerosion resistance of the coating were promoted.The main contents are as follows.(1)Based on the capillary induced microstructure shaping effect,a preparation method of durable Si C/fluorocarbon resin superhydrophobic coating was proposed.Fluorocarbon resin was selected as the film-forming agent,and the Si C particles modified with low surface energy were selected as the fillers.Interconnected hierarchical rough structure was constructed via the capillary cohesion resulting from the volatilization of the first component solvent.Combined with the programmed curing temperature,the capillary flow was inhibited and the Marangoni convection was enhanced via the the surface tension regulation of the second component solvent.As a result,the homogenized Si C/fluorocarbon resin superhydrophobic coating was prepared.Besides,a particle filling model of superhydrophobic coating was established,and the critical filler content for constracting the interconnected hierarchical rough structure was delivered.The surface topography,chemical composition,hydrophobicity,thermal conductivity,and the wear resistance of the coating were investigated.According to the results,the homogenized Si C/fluorocarbon resin superhydrophobic coating performed an excellent hydrophobicity,mechanical wearing resistance,and thermal conductivity.The comparison indicated that the simulated critical Si C filler content consists with the experimental results.(2)The effect on the surface charge dissipation and electrical trap distribution of the nonlinear electrical conductivity and surface rough structure of the Si C/fluorocarbon resin caoting were investigated.The nonlinear electrical conductivity of the Si C/fluorocarbon resin superhydrophobic coating was investigated,and the surface charge dissipation was investigated via the isothermal surface potential decay measurment.The electrical trap distribution of the coating was delivered utilizing the double trap model.Through the microstructure shaping via solvent volatilization,the effect on the surface charge dissipation and electrical trap distribution of the nonlinear electrical conductivity and surface rough structure were investigated individually.Results indicated that the electrical conductivity of the Si C/fluorocarbon resin superhydrophobic coating performed electric field adaptability,inhibiting the accumulation of the surface charge.The nonlinear electrical conductivity and rough structure of the Si C/fluorocarbon resin superhydrophobic coating contribute to the optimization of the electrical trap distribution,accelerating the surface charge dissipation.(3)The critical condition of the electric-field-driven motion of the water droplet on the Si C/fluorocarbon resin superhydrophobic coating was investigated.The electric-field-driven motion of the water droplet on the Si C/fluorocarbon resin superhydrophobic coating was observed via the shadow imaging technology,and the condensation performance of the coating under DC voltage was investigated though the Peltier temperature control platform.The adhesion work between the water droplet and the superhydrophobic surface was obtained by analysing the interfacial tension.Based on the Furmidge equation,the adhesion force between the water droplet and the superhydrophobic coating was obtained.Combined with the finite element analysis,the electrical driven force was caculated,and the critical condition of the electric-field-driven motion of the water droplet on the superhydrophobic surface was delivered.According to the results,the critical condition relates to the volume,the electrical conductivity,and the position of the water droplet,the electrical conductivity and the wettability of the coating also account.The comparison indicated that the simulated critical condition consists with the experimental results.(4)The surface flashover performance,electroerosion resistance,and their enhancing mechanism of the Si C/fluorocarbon resin superhydrophobic coating were investigated.Based on the filamentous carrier injection model,the effect on the surface electric field distribution of the nonlinear electrical conductivity and the electrical trap distribution of the Si C/fluorocarbon resin superhydrophobic coating were revealed.Combined with the electric-field-driven motion of the water droplet,the enhancing mechanism of the surface flashover performance of the Si C/fluorocarbon resin superhydrophobic coating was delivered.The electroerosion resistance of the Si C/fluorocarbon resin superhydrophobic coating was invesitigated,and the enhancing mechanism of the electroerosion resistance via the superhydrophobicity,thermal conductivity,and the nonlinear electrical conductivity was revealed.According to the results,the nonlinear electrical conductivity and electrical trap distribution could effectively relive the electric field distortion of the Si C/fluorocarbon resin superhydrophobic coating.Therefore,combined with the superhydrophobicity and the electric-field-driven motion of the water droplet,the surface flashover performance and electroerosion resistance of the coating were enhanced.The above results indicate that the prepared Si C/fluorocarbon resin superhydrophobic coating performs excellent hydrophobicity and surface electrical performance.The nonlinear electrical conductivity,the electrical trap distribution,and the electric-field-driven motion of the water droplets could enhance the surface flashover performance and the electroerosion resistance of the Si C/fluorocarbon resin superhydrophobic coating.As a result,the Si C/fluorocarbon resin superhydrophobic coating shows a prospected application potential,which is beneficial to improve the operation performance of the electrical power facility. |
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