Fabrication of hierarchical micro/nano structure surface on copper by EDM and its hydrophobicity
HE Zhao-rong1,2, JIE Xiao-hua1, LIAN Wei-qi1
1. School of Materials and Energy, Guangdong University of Technology, Guangzhou 510036, China;
2. College of Mechanical and Electrical Engineering, Guangdong University of Petrochemical Technology, Maoming 525000, Guangdong, China
Abstract：The hierarchical micro-nano structure surface on copper was fabricated by electrical discharge machining (EDM). The hydrophobic property was increased due to the hierarchical micro/nano structure (HMNS), which consisted of the micro/nano scale holes, molten balls, recast regions and the micro thermal cracks. The effects of the pulse width on the hydrophobicity of HMNS were investigated. The results indicate that with the increase of the pulse width, the quantity of the micro-nano scale holes increases. The distribution of other hierarchical micro structures is more homogeneous. The effective area of "air cushion" increases, which can trap more air in the HMNS. And the hydrophobicity of HMNS also increases. The proportion of the solid-liquid interface area (fsl) reduces. The contact area between the water droplet and "air cushion" in the HMNS increases. Therefore, the effect of the physical adsorption for the HMNS on the water droplet is weakened. The contact angles of the HMNSs can be increased up to (144.7±2.1)°, and the range of contact angle hysteresis is (8.46±3.3)°-(14.10±1.2)°.
何照荣, 揭晓华, 连玮琦. 电火花加工制备铜基微纳层次结构及其疏水性能[J]. 材料工程, 2020, 48(1): 144-149.
HE Zhao-rong, JIE Xiao-hua, LIAN Wei-qi. Fabrication of hierarchical micro/nano structure surface on copper by EDM and its hydrophobicity. Journal of Materials Engineering, 2020, 48(1): 144-149.
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