Research On Bionic Surface Wear And Fatigue Resistance Of Ball End Milling

The surface morphology of parts has an important influence on the service properties such as wear resistance,fatigue resistance and corrosion resistance.For example,the wear resistance and fatigue resistance of automobile panel die surface directly determine the forming quality and die service life.The concave and non smooth surface of some organisms in nature has good wear resistance.It is an effective method to improve the performance of the bionic non smooth surface with pits by laser processing.High speed ball milling can form pits with regular distribution,and has the advantages of high processing efficiency,wide operation range and low production cost compared with laser processing technology.Therefore,the effective combination of bionic non smooth surface theory and high-speed machining technology is of great practical significance to improve the safety service performance and prolong the service life of parts.In this paper,Cr12 Mo V,a commonly used material for automobile panel dies,is taken as the research object.Combined with its service environment and main failure forms,the wear characteristics and anti fatigue performance of bionic surface are explored based on the feasibility analysis of high-speed milling of bionic surface with the reference of pit shaped non smooth morphology of dung beetle body surface.Firstly,the bionic design prototype is based on the quadrangle pit shape of the body surface of dung beetle,and the non smooth surface shape of the pit is extracted and analyzed.From the aspects of debris collection,storage and torque effect,stress release,negative pressure drag reduction and rapid heat dissipation,the mechanism of drag reduction and wear resistance of bionic surface is analyzed;The retardation effect of bionic quadrilateral pits on fatigue crack growth was also analyzed.The feasibility of manufacturing bionic concave surface by ball milling is verified by ball milling experiment,and the relevant indexes are tested to meet the actual requirements of bionic surface morphology parameters.Secondly,the formation mechanism of feed residue and row spacing residue in ball head milling is analyzed,and the influence of machining parameters on the surface residual morphology is studied.The single factor milling experiment is designed to verify the accuracy and reliability of the simulation model of surface morphology and demonstrate the phase difference ?? The influence of the shape of the surface morphology micro cell crater is verified.The feasibility of the method of milling the spherical head to prepare the surface morphology micro element of the quadrilateral and hexagon concave is verified.Thirdly,through the use of research methods combining numerical simulation and friction and wear tests,the best friction reduction mechanism is selected from the aspects of stable friction coefficient,wear debris collection,storage capacity,stress dispersion and slow release,and heat exchange effect.The wear-resistant bionic surface shows that the quadrilateral pits on the surface of the dung beetle have the best drag reduction and wear resistance,and the friction coefficient is reduced by 23.6% compared with the friction coefficient of the polished specimen.The influence of different cutting parameters on the wear resistance of the bionic surface morphology was determined,and a combination of cutting parameters with good wear resistance was obtained.Finally,the correlation and influence mechanism between high-speed ballend milling bionic pit morphology and anti-fatigue performance are analyzed.Based on the Neuber model,a mathematical model between ball milling parameters,surface topography stress concentration factor and fatigue life is established.Theoretical analysis,simulation and experiment verify that the quadrilateral bionic pit surface has good fatigue resistance.In addition,from the perspective of fatigue crack growth,it is concluded that the quadrilateral pits on the surface of the bionic dung beetle have a certain retarding effect on the fatigue crack growth.Through the observation of the fatigue fracture of the bionic specimen,the relevant fatigue fracture information is obtained.