| In this article, the key work is to have the wettability of representative metal:Cu-Zn Alloyl surface improved.Many biology in nature show special wettability because of unique shape, structure on their skin and the difference of materials between body and outside surface when experienced millions of millions years evolution, such as duck belly feather shows superhydrophobicy as the interaction between spine barbs and surface lipoid; On the other side, some biology show superhydroplibicy. In the view of bionics, it is the result of coupling with modality, structure and materials.The research for solid surface wettabiltyt is focus on two directions: To make the hydrophilic surface change into hydrophobic or superhydrophobic surface or to make the hydrophilic capacity increase. Many progress have been made by constructing modality, structure and material bionic coupling surface in nonmetal area.Three ways were used to make hydrophilic metallic surface change to be hydrophobic surface: (1) To fabricate micro-nanometer scale nonsmooth modality. The first step is making self-assembly template, then depositing metal in the gap, at last removing template. The successful work is on Au surface by Mamdouh E.Abdelsalam. No report has been found in China. (2) To fabricate superhydrophobic metallic surface through the interaction of shape and material. Main ways include chemical eroding, anode oxidation, laser etching and so on. Then the low surface energy material was used to make a thin film on the surface. In this way, the duality bionic coupling surface was made, the metallic surface may be superhudrophobic; (3) To create new matter by chemical reaction.Opposite above, to make the capability increase by copying shape of biology skin come true, the main factors are had the contact area increased.On the hydrophobic metallic surface, water resistance would be low, bear the weight of ship or the velocity would be increase at the same cost or power; On the superhydrophobic surface, self-cleaning, anti-eroding, antipollution would be true. Hydrophilic metallic surface could be used at medicine, industry and so on. Up to now, research for wettability of metal has been the rush area in the world.Cu ? ZnAlloy and stainless steel is a kind of important industrial raw and processed material, It has been widely used to make pipeline, shafting and high strength parts of automobile and ship.In this work, we use laser photography, laser fine processing and nanometer technology to fabricate modality, structure duality bionic coupling metallic surface and modality, structure and material ternary bionic coupling metallic surface. By this way, Cu ? ZnAlloy surface is from hydrophilic to superhydrophobic successfully. On the other hand, Cu ? ZnAlloy and stainless steel surface hydrophilic capability increase by fabricating geometry non-smooth shape bionic surface. By our work, two directions progress are made.1.Geometry non-smooth shape has been fabricated by means of Patankar model on Cu ? ZnAlloy and apparent contact was test. It has been shown that the hydrophilic capability increase 62% or the apparent contact angle decrease from 82.5°to 31.5°. Linearity tropical equation is below Yi = 28 .0532+0.1730X1i +0.1918X2i+1.1165X3i+εiAmong factors a(x2i),b(x1i),H(x3i), the key factor is H. Even ifβ≥0.0632, hydrophilic surface can not change to be hydrophobic surface. Nonlinear mathematics model is belowForce model. When a droplet sits on a solid surface, thenWhere, cosθ* denotes apparent contact, R 0 denotes the radius of sphere water droplet,γdenotes surface tension, Px denotes efficiency force to water droplet, T denotes temperature, p denotes environment press, k is a coefficient, d denotes the distance between two molecules.2. To make Self-assembling model on Cu - ZnAlloy surface, then deposit pure Cu to the model interval, fabricate shape, structure and high surface energy material ternary bionic coupling metallic surface. Cu - ZnAlloy surface is changed from hydrophilic to hydrophobic. The apparent contact angle increases from 82.5°to 126.1°or increases 53%; The sliding angle is about 5°. In the process of fabricating bionic coupling surface, the key factor is the radioξand the solid area fractionΦs.The change of apparent contact is close to Cassis-Baxter model, it is not keeping step with Wenzel model. Function of pure Cu is fabricating non-smooth shape and composite structure.3. On the basis of above work, to fabricate shape, structure and low surface energy material ternary bionic coupling metallic surface. Cu - ZnAlloy surface is changed to be superhydrophobic. The apparent contact angle increases from 82.5°to 161.3°; The sliding angle is about 4.6°.4. Non-smooth stainless steelbionics surface has been fabricated by laser fine processing and hydrophilic capability has been increased 28.8%. The relationship between roughness factor r and apparent contact angleθ* isThe relationship betweenΦs apparent contact angleθ* is...
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