Preparation Of Amphiphobic Surfaces On Aluminum Alloy And Its Performance

Due to surface wear resistance of aluminum alloy is poor, application of this material has been restricted. This article aims to change the surface wettability of aluminum alloy, thus, to improve the surface tribological properties of aluminum alloy under water lubrication, provide a theoretical basis and technical support for manufacture aluminum alloy of amphiphobic and wear.In this paper, taking aluminum magnesium alloy as base material, using the combination of micro-structure and nanoparticles implanted on the surface, we prepared the amphiphobic surfaces with micro-nano structure,and studied its wettability and antifouling properties. Mechanical friction method was used to discuss durability of preparative hydrophobic/oleophobic surface, in order to provied new method for enhancing durability of aluminu alloy.Laser processing was used to build dot and grid micro-structures with spacing of 100μm on 5083 warship aluminum alloy surface, and the nano-SiO2 powders were coated on the micro-structures to build micro-nano structures for the superhydrophobic/oleophobic surface of aluminum alloy. The contact angles and roll angles were measured by contact angle measurement. The results show that the grid surface has the stronger superhydrophobic/oleophobic performance than that of dot, the water contact angle is as high as 159.9°nd the hexadecane contact angle is as high as 142.0°.Tribological performance was evaluated by CETR Universal Micro-Tribometer in water and oil lubrication. With the improvement of the hydrophobic/oleophobic performance, the friction coefficient decreases, the depth of the grinding crack becomes shallower and the width gets narrower. The friction coefficient under oil lubrication is significantly smaller than that of water lubrication, and the grinding crack is shallower and narrower. The friction coefficient of the dot surface is greater than that of the grid surface under water lubrication, while the friction coefficient of the dot surface is smaller than that of the grid surface under oil lubrication.The durability of the hydrophobic/superhydrophobic surface were tested by using the method of the sample load and friction slide on sand paper. The results show that the contact angles of polishing surface increase with increasing SiO2 concentration and up to 150.8°. But the surface has high adhesive force for the droplet. When the lengths of sliding is 10 m, the contact angles less than the original 72.3°; The surface with both amphiphobic and low adhesive force was fabricated by laser etched the grid or dot micro-structures. The grid surfaces have greater contact angles as high as 155.4°, and smaller roll angles only 0.34°. When the lengths of sliding is 10 m, the surfaces is still hydrophobic, and the grid micro-structure has greater durability.The preparation of hydrophobic/oleophobic surface dramaticlly enhance tribological properties of aluminum alloy.In seawater environment, testing corrosion resistance by the way of electrochemical analysis method which showed that:a double-layer structure of micro-nano amphiphobic surfaces can be improved aluminum corrosion impedance two orders of magnitude. This description the preparative hydrophobic/oleophobic surface to external forces and mechanical action possess superior durability and corrosion resistance.