Design And Grinding Method Of Gradual Spiral End Milling Cutter

In aerospace industry,titanium alloy materials are widely used in engine,frame structure,impeller blade and other parts.Titanium alloy material is the metal material with the highest specific strength,and has good strength to weight ratio,high temperature resistance and corrosion resistance.It can not only replace aluminum alloy for high-temperature applications,but also replace nickel based alloy or steel for corrosion prone applications.At the same time,titanium and its alloys are considered to be difficult to machine materials because of their low thermal conductivity,high chemical reactivity and low elastic modulus;This will lead to high cutting force,high cutting temperature,work hardening and other problems in the machining process.In order to solve the above problems,this paper designs a special tapered spiral end mill for titanium alloy side milling;The mathematical model of cutting edge and the grinding model of spiral groove are constructed.Based on the cutting edge model,combined with ABAQUS and NSGA Ⅱ genetic algorithm,the theoretical analysis,parameter optimization and experimental verification of tapered spiral milling cutter are carried out.The helix angle of the cutting edge of the tapered spiral milling cutter changes gradually,which is more complex than the traditional end milling cutter,so the traditional grinding model of spiral groove is no longer suitable for this type of milling cutter.According to the definition of generalized helix,the theoretical formula of gradual spiral cutting edge is derived,and the movable frame of cutting edge curve is established.Firstly,the grinding point of the grinding wheel is selected based on the movable reference frame,and then the grinding wheel coordinate is calculated to make the grinding point of the grinding wheel coincide with the origin of the movable reference frame after the first translation;Then the grinding wheel is rotated around the T-axis of the movable frame to obtain the front angle of the spiral groove,and the new movable frame is TBN;Finally,it rotates around the B axis of the new movable frame to meet the core thickness requirements.The 3D parametric modeling of tapered spiral end mill is carried out,and the modeling process and tool angle definition are described in detail,and the tool parametric platform is established.The platform integrates modeling,simulation,data storage and other functions by calling UG,ABAQUS,My SQL and other software,greatly shortening the tool design cycle.In order to obtain the best tool parameters and milling parameters,this paper uses this platform to carry out multi-objective orthogonal experiments on tool parameters and milling parameters.The optimal parameters of the tool are optimized by combining the simulation results of several groups of milling temperature and milling force values with the genetic algorithm.Finally,the grinding and milling performance experiment of tapered spiral end mill is studied,and the experimental results of chip shape,milling force,milling vibration and workpiece surface roughness are analyzed to verify the performance of the milling cutter designed in this paper.