Nanosecond Laser Polishing Titanium Alloy Ti6Al4V Mechanism And Experimental Study

Titanium alloys are widely used in aircraft engines,rockets,missiles and industrial electrodes,power station condensers,etc.due to their high strength,toughness and corrosion resistance.However,titanium alloys have poor process performance and difficult machining,and are a typical type of difficult-to-machine materials.Polishing titanium alloys can optimize surface quality,improve wear resistance and service life.Achieving precise and efficient processing of material surfaces is currently a problem faced by traditional processing technologies.In this paper,a nanosecond pulsed fiber laser was used to polish the titanium alloy Ti6Al4V.The experimental study of the titanium alloy Ti6Al4V polished by the nanosecond fiber laser with two different beams in air and the original surface roughness of the material in the argon atmosphere At the same time,the changes of the surface of the material after polishing and the mechanism of action.The specific research content and conclusions are as follows:?1?Nanosecond laser polishing experiment in air,the original surface roughness of titanium alloy Ti6Al4V Ra₀=0.23?m,using Gaussian beam and flat beam two nanosecond lasers under two pulse widths,changing other laser parameters Ti6Al4V surface influence law and mechanism.The results show that the surface roughness Ra after nanosecond laser polishing is 0.078?m,the reduction rate is 66%,the surface roughness that can be reached by the flat-top beam is smaller,and the surface morphology of the polished material is smoother.The pulse energy density increases,the more bump ablation,the surface roughness of the material decreases;the spot overlap rate increases,the surface roughness decreases,the overlap rate is too large,the surface roughness increases;the pulse width increases within a certain range,The surface roughness is reduced.The relative content of C element on the surface of the polished titanium alloy Ti6Al4V material decreases,and the relative content of O element increases.Only slight oxidation occurs on the surface of the material,which can quickly reduce the surface roughness of the material and improve the surface finish.?2?Nanosecond laser polishing experiments were carried out in an argon atmosphere.The effects of various parameters on the surface of the titanium alloy Ti6Al4V at three different titanium alloys with different surface roughness Ti6Al4V under different powers The results show that the original surface roughness of the material is an important factor affecting the polishing of the surface of the material.The greater the surface roughness of the material,the greater the absorption rate of the laser,and the greater the reduction rate of the surface roughness of the polished material.Ra0 is 1.78?m,the surface roughness of the polished material is at least 0.35?m,the surface roughness reduction rate is 80%,when the original surface roughness of the material Ra₀ is 0.4?m,the minimum surface roughness of the polished material is 0.17?m,the surface The roughness reduction rate is56%,and the relative content of O and C elements on the surface of the polished material is reduced.The results of the study can promote the polishing efficiency of titanium alloy and optimize the performance of titanium alloy.