Research On Back-electrolysis-assisted Laser Etching Technology Of Massive Micro-holes Oil Filter

With the rapid development of advanced manufacturing technology,aerospace systems have higher requirements for filter quality,weight and cost performance.At present,galvanometer-type laser equipment is widely used in the micro-hole processing of precision metal filters,but the defects such as thermal deformation and slag adhesion caused by laser processing will seriously cause the accuracy and consistency of the filter micro-holes.In this project,through the comparison and analysis of a large number of experimental results of laser direct processing,solution-assisted laser processing and electrolytic reaction-assisted laser processing,the special processing technology of back electrolysis-assisted laser drilling is proposed for the processing of massive microporous oil filters.The research content includes the following aspects:1.The mechanism of laser etching of metal materials is analyzed,and it is pointed out that defects such as micro-cracks will occur when the laser directly etches the metal;then the interaction between the laser and the solution is analyzed,and the electrolytic dissolution and corrosion of the metal on the backside are analyzed accordingly.Mechanism of action.2.According to the action mechanism of solution-assisted laser processing on the back surface,a comparative experimental study of laser processing and water-assisted laser processing on the back surface was carried out.Firstly,the quality of the micro-holes obtained by the two processing methods under the same parameters is compared,and it is pointed out that the backside solution-assisted method can obtain micro-holes with smaller taper,better hole type,less slag and recast layer.Then,the influence of laser parameters on the taper and surface morphology of the micro-hole is analyzed through orthogonal experiment and single factor experiment of five factors and four levels.The results show that the laser power and the number of elements have the most significant impact on the taper,and the scanning speed and defocus are relatively small;reducing the laser power,total processing times or increasing the pulse frequency and scanning speed within a certain range can all increase The surface quality of the micro-holes,but too much change will greatly increase the taper.3.Aiming at the special case of massive filter mesh holes,in order to obtain thousands or even tens of thousands of high-quality micro-holes in a short period of time,the traditional concentric circular laser scanning path was firstly tested for path optimization;then it was proposed to measure the mass by variance Hole consistency method,design orthogonal test of five factors and four levels to study the influence of laser parameters on the consistency of massive holes.From the results,it can be seen that the defocus amount and scanning speed have the greatest influence on the consistency of the massive micro-holes,and the number of concentric circles and the laser power have the least influence.Therefore,in the actual production and processing process,it is not advisable to greatly change the laser defocus amount and scanning speed.Finally,a set of full factor test results were compared with the hole taper,the consistency of the hole and the processing time of the thousand holes,and the best parameters were obtained,and 40480 highquality holes were successfully processed in an area of 30×20 mm.4.According to the test results of the solution-assisted laser processing on the back surface,the back electrolysis-assisted laser etching micro-hole test was carried out.First,the advantages and feasibility of laser-electrochemical composite etching of micro-holes are analyzed,and the micro-hole morphology and hole wall quality of laser direct processing,back water-assisted laser processing and back electrolysis-assisted laser processing are compared;then electrochemistry is studied.The influence of parameters on the micro-hole taper and group micro-hole machining efficiency.The results show that the processing technology of back electrolysis-assisted laser processing can improve the quality of the micro-holes while reducing the taper of the micro-holes.Choosing appropriate electrochemical parameters can greatly improve the processing efficiency of a large number of holes.This subject researched the special processing technology of aerospace kerosene filter element,provided a novel filter processing technology,and successfully prepared various types of oil filter.At the same time,the feasibility of laser electrochemical combined processing technology in high-precision filter processing is deeply explored,which has certain theoretical significance and practical application value.