Study Of Jet Electrodeposition Assisted Micro-narrow Slot Mask Electrochemical Machining

Array micro texture can not only reduce the contact area of friction pairs but also store intertexture lubricating oil.As a result,friction and wear performance on the surface of friction pairs is improved.Jet electrodeposition has been widely applied in many fields because of its fine coating grain and excellent surface performance,which thanks to its high-speed plating solution velocity,fast ion deposition,etc.According to combine jet electrodeposition technology with surface texture technology,well-performed texture coating can be fabricated.What's more,due to its good hardness,wear resistance and corrosion resistance performances,Ni-P-ZrO₂ composite coating has a wide application prospect.In this paper,a novel technique method for micro texture Ni-P-ZrO₂ composite coating was proposed.Firstly,side flow photolithography electrolysis was used to fabricate micro-narrow slot array on 45 substrate.Then Ni-P-ZrO₂ composite coating was prepared on micro-narrow slot array by jet electrodeposition.Finally,micro morphology,surface performance,friction and wear performance of micro-narrow slot array on Ni-P-ZrO₂ composite coating were analyzed in general.The main research content is as follows.(1)Constructed of the test platform.In order to fabricate micro-narrow slot array coatings,test platform including electrodeposition device and ECM device was set up.This paper,mainly designed special fixture and nozzle on account of shape and size of workpiece to enhance the reliability and order of experiments.(2)Multi-physics coupling simulation of side flow photolithography electrolysis.Simulations of ECM process under different technological parameters were carried out and analysis on simulation results was conducted.Based on COMSOL Multiphysics software,models of turbulent flow field,temperature field,electric field and dilute material transfer field were built respectively.Then a coupled multi-physics model was formed according to set the relationship among the four fields.By using this kind of model,ECM simulations of different parameters were completed.In this paper,micro-narrow slot ECM processes under 5V,10V,15V,20V and 5s,10s,15s,20s were investigated respectively.By analyzing changes of micro-narrow slot morphology,parameter range of electrolytic process tests was determined:processing voltage 5-15V,processing time 5-20s.In real tests,parameter interval should be decreased.(3)Process tests of side flow photolithography electrolysis of micro-narrow slot array.On the range of test parameters determined by simulation,single factor experiments were carried out.Effects of processing voltage and processing time on micro-narrow slot depth,width and roughness of bottom profile were investigated respectively.Contrastive analysis results show that optimized parameter of micro-narrow slot array photolithography electrolysis is processing voltage 12.5V and processing time 10s.(4)Process experiment study of surface jet electrodeposition of Ni-P-ZrO₂ composite coating on micro-narrow slot array.At first,preliminary experiment was carried out to optimize process parameters of micro-narrow slot array coating preparation.Influences of current and plating solution flow velocity on coating performance were investigated mainly.Ideal process parameter for well-performed micro-narrow slot coating was obtained,current 0.6A.flow velocity 4m/s,injection interval 2mm,plating solution temperature 60?,anode scanning velocity 1000mm/min.Based on this,effects of different ECM process parameters,processing voltage and processing time,on coating morphology and performance were investigated by comparative analysis of morphology and binding force.Results show that in same jet electrodeposition process parameter.Lithography electrolyzing under 12.5V for 10s can fabricate micro-narrow slot array with best surface performance.The conclusion is that ECM fabricated micro-narrow slot section performs better,coating prepared on this array structure performs better.(5)Surface characteristic research of micro-narrow slot array Ni-P-ZrO₂ composite coating.Under the same experiment condition,friction and wear properties of 45 substrate,45 micro-narrow slot array workpiece,Ni-P-ZrO₂ composite coating on 45 surface,micro-narrow slot array Ni-P-ZrO₂ composite coating on 45 substrate were contrastive analysis.It can be found that under the same experiment condition,micro-narrow slot array Ni-P-ZrO₂ composite coating on 45 substrate has better friction and wear performance.In conclusion,micro-narrow slot array coating could improve friction and wear performance of workpiece,but it might reduce the binding force between coating and substrate to some extent.