Research On Chemical Etching Of Metal Microgroove Array On The Surface Of Rotating Body

The microstructure array on the surface of the rotating body has the advantages of compact arrangement,wear resistance and resistance reduction,which endow the parts with the characteristics of light weight and good performance.It can be used in many fields such as precision forming,surface modification,electronic communication and so on.Chemical etching has attracted much attention because of its advantages such as simple operation,low cost,good uniformity,easy machining size control and good surface morphology.In the process of microstructure etching,the amount of lateral erosion is an important index to measure the etching quality.In order to solve the problem of serious lateral erosion in chemical etching process,a method to improve the etching quality of microstructure array by using post-etching polishing process was proposed in this paper,and it was applied to the chemical etching of microgroove array on the surface of rotating body.Firstly,based on plane chemical etching,the influence of different experimental conditions on the lateral erosion of the linewidth of the microgroove array was investigated.Secondly,the cellular automata method was used to simulate the etching morphology of microgroove under different conditions.Then,based on the results of the plane chemical etching experiment and simulation model prediction,a microgroove array with small linewidth,small lateral erosion and good uniformity was fabricated on the surface of the rotating body.The specific research contents of this paper are as follows:(1)Based on the dissolution and passivation process in the chemical etching of stainless steel,the factors influencing the lateral erosion of microgroove array were analyzed.The process of metal etching and the lateral etching phenomenon was analyzed,and then the cause of the lateral etching phenomenon was clarified.The dissolution and passivation process in the chemical etching system ofFe Cl₃ solution and stainless steel were studied,and the forming conditions and structural composition of passivation film were discussed.Finally,the common methods to reduce the lateral erosion of microgroove array were discussed.(2)In order to determine the influence of different conditions on the amount of microgroove array lateral erosion,the basic experiment of plane chemical etching of 304stainless steel was carried out.The exposure dose was optimized by exposure experiment,and the structure of the etching mask with good size was obtained.And the effects of different experimental parameters and post-etching polishing process on the lateral erosion of microgroove array were studied.The experimental results show that the lateral erosion of the microgroove array decreases with the increase ofFe Cl₃ concentration,decreases first and then increases with the increase of HCl content,and increases with the increase of temperature.The post-etching polishing process can significantly reduce the lateral erosion of the microgroove array,and the depth loss is only 2%of the depth of the microgroove array.(3)In order to predict the morphology of microgrooves under other conditions,the simulation of microgroove chemical etching process was carried out based on the cellular automata method.The simulation model was established and the local rules of cell were established.The simulation parameters were set and modified through the experimental data.Then the etching morphology of stainless steel microgrooves under different conditions was simulated.The results show that the simulation results are consistent with the experimental results,and the relative error is less than 10%.Finally,the simulation model was used to predict the influence of photomask linewidth on the lateral erosion of the microgroove.(4)Based on the above research results,a microgroove array on the surface of the rotating body was fabricated.A method of preheating,wet pressure and slow speed film laminating was put forward to solve the problem of poor film laminating quality during processing.Then a microgroove array with an average linewidth of 59.1?m and an average depth of 15.5?m was fabricated on the surface of 304 stainless steel rotating body.The microgroove array has good uniformity and the linewidth relative error between the microgroove array and the mask is as low as 1.5%.