| In the process of drilling into the ice,the problem that the efficiency of drilling is affected by the icing and thawing is urgent to be solved.The superhydrophobic coating has good anti-icing property due to its special composition and low surface energy.Polytetrafluoroethylene?PTFE?coatings have high chemical stability,thermal stability,excellent electrical insulation property and self-lubricating property.It is widely used in the preparation of hydrophobic coating,but its mechanical property and wear resistance are poor.In this paper,by adding the Ceria?Ceria?,silica?SiO2?modified PTFE coating,we prepared different compositions of Ceria/PTFE,SiO2/PTFE composite coatings by one step spraying on the 45steel substrate.The water contact angles?WCAs?of the coatings were measured.The surface morphologies of the coatings were observed by scanning electron microscope?SEM?and 3D laser measurement microscope.Hydrophobic and wear mechanism was analyzed.The main results are as follows:?1?PTFE composite coating modified by Ceria has excellent hydrophobicity and wear resistance.5wt.%Ceria/PTFE composite coating has the lowest friction coefficient with the lowest value of 0.1143 and the lowest wear rate of 0.388×10-4 mm3/Nm.The wear rate is 80.6%lower than that of pure PTFE coating.And it has the highest contact angle which is 134°.As lanthanide rare-earth oxide,Ceria has the unique electronic structure,which makes Ceria hydrophobic in nature.Therefore,the composite coatings has excellent hydrophobicity.At the same time,Ceria has high hardness and good tensile resistance,so an appropriate amount of Ceria added into PTFE improved the wear resistance of the coating.?2?When the mass fraction of SiO2 was 10%,the friction coefficient of SiO2/PTFE composite coating reached the lowest value of 0.119,and the wear rate was 0.48×10-4mm3/Nm reaching the minimum value,which is 75.8%lower than that of pure PTFE coating.Meanwhile,the contact angle of SiO2/PTFE composite coating increased to129°,showing good hydrophobicity.The uniform mastoid structure on the surface of SiO2/PTFE composite coating may be the reason for its good hydrophobicity.In the composite coating,SiO2 nanoparticles with appropriate mass fraction are well bound to PTFE,and SiO2 nanoparticles with higher strength may be an important reason to reduce wear. |
PDF Full Text Request