Material Removal Mechanism Of Laser-assisted Micro-milling TC4 Based On Burr Morphology

Titanium alloys are more and more widely used in aerospace and medical equipment,but their machinability is relatively poor,which seriously affects the service life of tools.Laser-assisted micro-milling(LAMM)is an excellent processing method for difficult-to-machine materials such as titanium alloys.It uses a laser thermal field to heat and soften the materials to reduce cutting force,reduce tool wear,and increase material removal rate.In addition,the laser-assisted micro-milling equipment is relatively simple,and has good application value and application space.However,the laser-assisted processing of softened materials will cause the size of the burrs to become larger during processing,especially during micro-processing,the relative size of the burrs is large,which seriously affects the surface quality.This paper mainly studies the burr generation mechanism and active control method of laser-assisted micro-milling process.First of all,based on the minimum cutting thickness model of the milling process,the burr size model during chip separation is established,and the influence of the laser thermal field on the model is fully considered to modify the theoretical model.Deduced separately from the perspective of energy and work,and explored the performance of the size effect of laser-assisted micro-milling on the size of the burr.Then,establish the laser thermal field simulation and introduce the obtained temperature field results into the simulation model.Through the two-dimensional milling finite element analysis(FEA),the tool rake angle,tool back angle,tool population radius and other factors are simulated to observe the exit burr height.Analyze the influence of tool geometry parameters on the burr size,and compare the changes after introducing the laser temperature field.Through the three-dimensional milling model,the spindle speed,feed per tooth,milling depth and other parameters are simulated,and the size law of entrance burr,exit burr,up-milling burr,down-milling burr,and changes after the introduction of the laser temperature field are observed.Improve the temperature-related material parameters and further optimize the finite element model to make the simulation results more accurate.Finally,conduct a titanium alloy laser-assisted micro-milling experiment,using a single-factor variable research method,conduct a laser-assisted micro-milling experiment on a self-built small precision milling machine,and explore the influence of factors such as spindle speed,milling depth,and feed per tooth on the burr size High impact.Observe the surface morphology of the workpiece through a light microscope to obtain the relevant data of the burr size.And further explore the effect of laser power on burr size,obtain experimental cutting force data,fully explore the relationship between cutting force and burr size,and then explore the impact of various cutting parameters on burr size.It also proposes a processing method to reduce the size of the burr or suppress the generation of the burr to improve the processing quality.