Numerical Simulation And Experimental Study On Laser Trepanning Drilling Of Nickel-based Superalloy

Compared with the traditional way of drilling,laser drilling has been widely used in industrial applications because of its unique advantages.Because of the wide application prospect and high research value of laser drilling,many scholars have devoted a lot of research to it.In this paper,the method of control variable adopted and taking GH4133 superalloy as the research object,the theoretical analysis and experimental research of laser trepanning drilling technology carried out systematically.Firstly,this paper briefly introduces the laser drilling technology,the GH4133 material,the advantages of laser drilling,the laser drilling method,the current research status and development trend at home and abroad.At the same time,the mechanism of laser drilling is expounded in detail from the characteristics of laser beam,the process of laser drilling,the general rule of interaction between laser and material,the formation and influence of photoinduced plasma,and the principle of laser trepanning drilling.Secondly,based on the basic theory of heat transfer,the temperature field model of high temperature alloy material laser trepanning drilling was established by using the finite element software ANSYS.The programming language of APDL were used to program the numerical simulation of the laser trepanning drilling process,and get the profile of the hole with the change of the number of pulses and the distribution diagram of the temperature field.Through the built-in solver of ANSYS software,the hole depth under different pulse numbers and the upper aperture under different pulse energy are solved.The results show that the depth of ring hole increases with the increase of pulse number,and the upper aperture increases with the increase of pulse energy,which is consistent with the result of drilling experiment.Finally,the experiment used the DMG CNC precision laser processing center equipment and conducted laser trepanning drilling experiment on the superalloy GH4133.The effects of pulse energy,defocus,pulse width,ring number,auxiliary gas pressure and ring cutting speed on the quality of laser ring cutting are systematically studied.The quality indexes in the experiment include the surface morphology of microporous surface,the upper and lower aperture size,the shape of the hole section,the taper and so on.