Preparation And Properties Of 304 Stainless Steel Super-hydrophobic Surface

304 stainless steel has a wide range of applications in the industry and marine industry because of its good mechanical and corrosion resistance.However,marine algae and shellfish will attach to the hull surface,which increases the resistance of the ship in the water.The state spends a lot of money to clean the hull surface every year.In addition,although 304 stainless steel has a certain corrosion resistance,it is not corrosion-resistant.The corrosion of stainless steel causes environmental pollution and waste of metal resources every year.However,if 304 stainless steel surface has high super-hydrophobic property,it can effectively reduce the biological bonding,friction and wear,metal corrosion,so how to make its surface have super-hydrophobic property has attracted great attention of scientists.In this paper,the super-hydrophobic coating on 304stainless steel was prepared by laser engraving and spraying,and its super-hydrophobic properties and formation mechanism were studied.（1）Firstly,the influence of surface modification parameters on super-hydrophobic properties was studied.The surface of 304 stainless steel was constructed by laser engraving method,and then the surface was modified by perfluorosilane solution diluted with ethanol to study the optimal surface modification time and temperature.It was found that when perfluorosilane was used to modify the surface of laser engraved stainless steel,when the modification time was 5h,the modification temperature was 5h When the temperature is 45℃,the effect of modification is the best.（2）In the study of the influence of the surface micro texture shape on the super-hydrophobic properties,it is found that among the five micro texture shapes,when the micro texture shape is matrix column shape,the surface static contact angle（WCA）is the largest,reaching 165°.When the surface corrosion rate was measured,the value of matrix column shape corrosion rate was 4.198 mm·a^-1.In terms of friction resistance,the minimum friction coefficient of matrix column array shape modified on the surface was only 0.16.It is found that the WCA value is related to the ^f1 value of the matrix column array on the surface.The smaller the ^f1value is,the larger the WCA value is,which also corresponds to the experimental data.In the corrosion resistance test,we found that the corrosion rate of stainless steel surface decreased gradually with the increase of WCA value,because the larger WCA is,the smaller the contact area between water drop and stainless steel solid is,the less the exchange rate between ions and the corrosion rate is.（3）In the study of the super-hydrophobic property of the micro texture spacing,it is found that when the spacing a is 60μm,the WCA reaches the maximum of 157°and the sliding angle（SA）is the minimum of 7°.However,with the increase of the dimension,the WCA becomes smaller and the SA becomes larger and larger.The size of the pit array is 80μm in a,and the WCA reaches the maximum of 156°and the SA is the minimum of 5°.According to the prediction of the model,a=40μm is the largest WCA,but the actual measurement value is smaller than a=60μm,because the laser radius is too large and does not form the shape of matrix column itself.When the value of a is greater than 60μm,the matrix column can be formed.When a>60μm,the model can well predict the change of WCA value with the change of spacing a.（4）In order to realize the industrial preparation of super-hydrophobic coatings on stainless steel,three super-hydrophobic coatings containing Fe,C_O and Ni were prepared by spraying.These three coatings have higher WCA and smaller SA,which can realize super-hydrophobic and self-cleaning functions The WCA with Co coating is the largest,reaching 163°,SA is the smallest,and its self-cleaning effect is the best.And the three coatings have good stability and wear resistance in natural environment.In the experiment of anti adhesion,although the WCA on the surface of the coating decreased,it was found that the WCA on the surface of the coating was more than 150°within 20 times of adhesion,and the coating containing Fe powder tended to be stable with the increase of adhesion times,and the anti adhesion effect was the best.Moreover,in the anti-corrosion test,the three kinds of coatings can protect the metal surface from corrosion and have a good market application value.