The Research Of Lubrication And Friction Characteristics In Cold Extrusion Process Of Spur Gear

Spur gear is one of the most commonly transmission parts in automobile,and it has large market demand,generally being manufactured by cutting process.With the development of precision plastic forming technology,more and more spur gears are manufactured by the near net shape forming method.The gear that is made by cold extrusion,has high quality,high performance integrated,high production efficiency and high material utilization,therefore making straight tooth cylindrical gear by cold extrusion technology has broad application prospects.In cold extrusion process,due to the pressure of die and billets,friction on the contact surfaces has effect to part's quality and die life.Measuring reasonable lubrication is particularly important,so the study of lubricant for cold extrusion is great significance.In this paper,a truck with large modulus spur gear for the study,according to the structural characteristics of the gear,putting cold extrusion forming technique and using the finite element analysis and mathematical method to analyze forming regularity of spur gear of cold extrusion.And using friction and wear testing and scanning electron microscopic studies to study novel Nano-TiO₂ lubricant.The main research is as follows:?1?According to the structural characteristics of spur gear,combined with the advantages and disadvantages of common forming technology for spur gear,cold extrusion process is selected as the forming method of large module gears.paper achieved numerical simulation and analysis the relevant law on the part during cold extrusion process by DEFORM-3D software.?2?The paper researched the influence of the main process parameter on spur gear forming quality and forming load during the cold extrusion process.Then,Through numerical simulation and experiment design,based on response surface optimization method,to forming load,and tooth top collapsed angle volume and bottom surface outside convex as optimization target,on main process parameter for more target optimization design.The study obtained the optimal parameters.?3?Through study the lubrication theory of plastic forming and existing Nano particles of lubrication mechanism,using physical dispersed and chemical dispersed method to study Nano TiO₂ particles of sTable dispersed,the paper initially has made good dispersed effect,and has completed the preparing of the Nano TiO₂ lubricant.Through friction and wear testing and scanning electron microscopic,the paper researched the lubrication performance of new lubricant.