| Functional surface originates from organisms in the nature of the bionic manufacturing,self-cleaning properties of lotus leaf,shark skin drag reduction characteristics,catchment properties of spider silk and butterfly wings bright color for the design of bionic structure provides a new train of thought.The study found that the organisms possess these features are associated with the micro-nano structure of surface,it is the different combination of the micro-nano structure changed materials,such as optics,mechanics and invasive.Therefore,in the search for a simple and efficient micro-nano machining method for the preparation of biomimetic surface is of great significance.Femtosecond laser because of its unique super fast and super high and super advantages,obtained the widespread application in recent years,as a traditional processing provides a new train of thought,which provides a new way for the manufacturing sector.Especially in the field of micro-nano processing,femtosecond laser unique nonlinear machining process,improving the machining accuracy can be achieved material surface processing size of the sub-micron feature and the internal three-dimensional processing,unique advantage makes the femtosecond laser machining is gradually applied to the functional surface manufacturing.In this study,we use based on slit spatial light plastic method of femtosecond laser machining,laser parameters is studied to the influence of surface structure,realizes the surface morphology of controllable regulation,and further study on the large area processing applications in the field of special infiltration characteristics.In this paper,the main research work and innovation points can be summarized as follows:(1)With femtosecond laser slit spatial light plastic processing method instead of the traditional laser direct writing micro-nano processing,realize the material processing morphology controllable silicon surface control.First of all,the Matlab to simulate the process of slit plastic Fresnel diffraction,and experiments verify the feasibility of slit plastic,consistent with the change trend of simulation results.As the slit width increase gradually,the axis of the anisotropy topography gradually decreases,and short axis gradually increase,shaft rate gradually decreased.(2)Using slit plastic device further to adjust and control of surface topography,including the polarization direction,pulse number and the change of the laser energy affect processing morphology.We found that the change will only affect the pulse number and the laser energy processing depth,had a little effects on morphology of shaft rate;And the change of the polarization Angle can realize processing morphology by anisotropy to all the gay.In the slit width is fixed,the polarization Angle increased from 0 ° to 90 °,the morphology of the shaft rate gradually decreased,especially when the slit width is 1 mm shaft rate decreased most,fell to 2.60 from 4.05 or so.This kind of phenomenon produced due to slit plastic and surface plasmon scattering effect.(3)In the research on the surface of slit plastic structure regulation,on the basis of using point front method and the time of flight method to large area processing,processing materials including silicon and PDMS.Study found that law in the use of some large area processing materials,silicon anisotropic seepage characteristics of machining surface increased with the increase of pulse number increases gradually,up to 12 ° or so,when using the time of flight method processing silicon,results in better hydrophobicity;When using the time of flight method in PDMS surface of large area processing,contact Angle can above 150 °,realize super hydrophobic.Finally embarks from the Wenzel model,the change of the characteristics of the infiltration mechanism of explanation. |
PDF Full Text Request