Study On The Anti Frictionperformance Of Medicaltools Based On Bionic Microtexture

In the process of fracture treatment,the bone needs to be pre drilled in order to implant the fixator.The quality of predrilling will affect the stability of the fixture.In order to obtain an ideal drilling process,the key is to reduce the friction between the tool and the cortical bone and the resistance of the tool in the cutting process.In recent years,the research of surface texture shows that reasonable surface texture can play a good role in reducing friction and improving the friction reduction performance of the tool,which provides a new idea and new research direction for improving the cutting performance of the tool by changing the surface micro geometry of the tool.In this paper,the laser marking technology is used to prepare the bionic micro texture with different parameters on the front face of the tool.The effect of the bionic micro texture on the friction reducing performance of the twist drill is studied through the experiment of drilling cortical bone and the abaqus simulation software.The specific research contents are as follows:(1)After reading the literature of bionics and surface texture,we are familiar with the friction reduction mechanism of bionic micro texture under different lubrication conditions.On this basis,a new type of bionic micro texture crescent is obtained by observing the internal structure of pitcher.(2)The biomimetic micro texture is made by laser technology on the front face of the cutting tool.Because of the existence of the biomimetic micro texture,the contact area of the chip passing through the front face will be changed.Based on this point,the mathematical model between the axial force and the parameters of crescent bionic micro texture is established,and then the mathematical model is analyzed with MATLAB software.(3)To establish the experimental platform of cortical bone drilling.Under the condition of dry cutting,the influence of different parameters of biomimetic micro texture on the axial force and chip shape in the process of drilling cortical bone was studied by comparing with the tool without micro texture.The experimental results show that the bionic micro texture tool can reduce the axial force in the process of drilling cortical bone and improve the friction reducing performance of the tool.(4)Through the ABAQUS simulation software,the simulation model of cortical bone was established,and the influence of stress and axial force on cortical bone was further studied.The simulation results show that the stress and stress distribution of cortical bone are different in different stages.Because of the existence of biomimetic micro texture,the stress of cortical bone is more uniform,the stress gradient is reduced,the stress concentration of cutting part of cortical bone is reduced,and the axial force is smaller.