The Fabrication Of Micro/Nano Structure On Metal Substrate Surfaces And The Study Of Their Performance

With expanding application of metals and their alloys, the lack of comprehensivemechanical properties of materials is more and more obvious. It has become a keyproblem urgently to be solved to improve their comprehensive properties such assurface wettability, wear resistance and corrosion resistance because of the widespreaduse in various fields. In view of the above problem, this paper constructs differentmicro/nanostructure on metal surfaces which has the vital significance in enhancingmetal performance to unify the surface superhydrophobic self-cleaning properties,corrosion resistance and reduce the flow resistance. Moreover, this is also a furtherstudy research to provide wider space of potential applications for the preparation ofsuperhydrophobic surface. This paper has carried on the research and exploration ofthe following several aspects:（1）Regular hetero-hierarchical micro/nanostructure array composed ofmicroprotrusion-like Cu and dendrite Ag has been fabricated on Cu foils by combiningphotolithography techniques with primary cell-induced deposition and galvanicreplacement methods, which is based on the exploring of the roughness on coppersubstrate surfaces. This method changed the disordered structure of previous surfaceinto array surface innovatively and we also explore the effect of reaction time,concentration of solution and the other factors on the morphology. The results showed:for the template with pitch and diameter both are8μm, the surface wettability of bestvalue when deposition in0.2M CuSO4solution for six minutes and then reduction in0.02M AgNO3solution for70seconds. As can be seen from SEM vertical andcross-section graph, surface structure improved from single micron grade coarse tomicro/nano composite structure, and both morphology have good homogeneity andarray distribution, which is advantageous for the morphology control. The compositionof the rough surface structure and the crystallographic orientation were analyzed byXRD diffraction. The Cu and Ag map analysis and EDX map correspond to the elementSEM area further illustrates the composition and distribution of the interface. （2）For the wettability research of the two typical morphology, in this paper aseries of super hydrophobic performance metrics were tested including static anddynamic contact Angle, rolling Angle, droplet bouncing behavior, evaporation, therelationship between impact velocity and contact time, and the relationship betweendroplet diameter and contact time, the effect of super hydrophobic meter used in thesurface SERS enhancement and so on. Two models (Wenzel and Cassie-Baxter model)of liquid and solid surface wettability used for explaining the phenomenon andtheoretical analysis. The above experimental results were validated by modelsimplification and calculation and illustrated the contact angle of the correspondingtheoretical model of the droplet under two kinds of morphology, respectively.（3）Finally, we studied the corrosion resistance of the micro-nano fractaltopography on the surface. For the different pH of the aqueous solution the samples′outstanding superhydrophobicity showed the long time stability of the surfacemorphology. We can see the corrosion resistant performance of the processed surfacehave develop a lot according to the stability of the samples on the strong acid, strongbase solution and the simulating water solution.（4）The paper explores the preparation of superhydrophobic surfaces ofAl alloymetal by comparing the three wet chemical etching method,the single hydrochloricacid etching, SDBS/HCl solution etching and HF、HCl solution etching step by step.The factors（etching liquid concentration, the adding of the auxiliary etching agent,etching time and surface treatment means）which affected the aluminum alloy surfacemicro-nano rough topography and their performance were studied.（5）The friction and wear properties of the microstructures surfaces and couplingsurfaces sliding against GCr15steel ball (Hardness HV=15GPa, roughness Ra=0.01μm) when the load was1.65N. The worn surfaces microstructures, wear debris andwear mechanisms were analyzed by scanning electron microscopy (SEM), fieldemission scanning electron microscopy (FESEM). Results showed that surfacemorphology etching on hydrochloric acid solution which adding surfactants achieves agood combination of surface wettability and tribological properties.