Theoretical And Experimental Study On Low Frequency Vibration Assisted Milling Of Surface Microstructure

With the development of modern science and technology,parts with special microstructure surface have been widely used in aerospace,biotechnology,medicine,measurement and military fields.The research on high efficiency and high precision machining of surface microstructure has been paid more and more attention by domestic and foreign research institutions and experts.At present,the high efficiency and high precision machining of surface microstructure has become an important symbol of the competitiveness of a national system.The surface processing methods of microstructure include rolling forming,lithography,laser direct writing,lithography and ultra-precision machining.Rolling forming has the advantages of rapid forming speed and high yield value.However,the shape and size of the blank body are completely dependent on the cavity formed by the rolling head and die surface,and the forming pressure is large and the extension deformation is large.Lithography is a main process in the production of planar transistors and integrated circuits.It is a process technology that transfers circuit graphics to the surface or medium layer of single crystal to form effective graphics window or functional graphics.However,the processing materials are single,and are often used to process silica crystals.Laser direct writing is one of the main technologies for diffractive optical elements.The relief profile required on the surface of the anti-corrosion layer can be formed with the precision of submicron,and the requirements for processing equipment and environment are high.The ultra-precision machining method can realize the processing of complex geometric surface morphology such as 3D microstructure,and the processing materials are diverse(aluminum,copper,steel,alloy,ceramics,etc.),so this paper combines the advantages of vibration assisted machining in ultra-precision milling system.A set of aerodynamic and constant force milling tool system assisted by radial micro motion is used to provide low frequency two-dimensional vibration to milling the surface of micro structure of various materials.The main contents of this paper are as follows:(1)The kinematics model of the micro motion platform in the tool system is established.The mathematical model of the relationship between the input voltage and the output displacement of the micro motion platform is established by experimental research and Z-XY multiple polynomial fitting method;By using the optimization method,the error rate between the output displacement and the theoretical model can be lower than the required upper limit.(2)The influence of processing parameters(spindle speed,cutting pressure and voltage model)on the accuracy of the output displacement of the micro motion platform in the system is studied and analyzed by orthogonal experiment method.The optimal processing parameters combination of magnesium aluminum alloy,peek and stainless steel are analyzed,and the primary and secondary factors of each parameter on the experimental results are analyzed.(3)The profile of different size milling cutters on the surface of magnesium aluminum alloy and stainless-steel workpiece is measured by using VHX-900 of Keith,and the deviation between the profile error and the input theoretical profile is analyzed,that is,the profile error and unit error.The contour errors of two kinds of materials are compared under the same conditions.(4)The array microstructure of stainless-steel scalpel surface was processed to verify whether it has surface function and whether the surface hydrophobicity is better than that before processing.In a word,through the research of two-dimensional vibration assisted milling tool system,the network model of the relationship between input voltage and output displacement of micro platform,the optimal combination of different material processing parameters and the processing method of hydrophobic surface are obtained.