Study On Precision Electrochemical Grinding Of Micro Holes In High Elastic Alloy Steel 3J33B

Electrochemical grinding is a kind of composite processing technology which is used in both electrochemical machining and mechanical grinding.It has the advantages of both electrochemical machining and grinding,and shows great adaptability in the processing of difficult materials.It is possible to achieve high precision and low stress machining of micro holes on difficult to machine materials by properly matching electrolysis and grinding.At present,the research of electrochemical grinding composite machining technology mostly focuses on the research of machining technology and equipment,and the research on the effectiveness of composite machining is less,and there are many factors,so the research on the effectiveness of composite machining is of great significanceIn this paper,the electrochemical grinding technology of 3J33B micro hole of high elastic alloy steel is studied.The polarization and passivation characteristics of the material are analyzed.The experiments of the electrochemical grinding of the micro hole are carried out on the material.The main research contents are as follows:(1)The polarization characteristics of workpiece materials in different blunt electrolytes were tested by electrochemical workstation.The influence of electrolyte composition and concentration on the polarization characteristics was studied.The surface properties of workpiece after potentiostatic polarization were analyzed,and the electrolyte easy to form dense and uniform passivation film was selected(2)An electrochemical experiment platform was developed to study the influence of electrochemical parameters(time,voltage,electrolyte concentration)on the thickness and morphology of passive film,which provides a basis for quantitative analysis of passive film in actual processing.The thickness of passivation film is predicted in the actual machining,which provides the basis for the selection of process parameters of precision electrolytic grinding and improves the machining efficiency and quality.The element composition of passivation film was detected by EDS,and the main components and passivation mechanism of passivation film were studied.The hardness changes before and after passivation were analyzed by microhardness tester to verify the low loss of grinding wheel in ECM.(3)In order to ensure the effectiveness of the composite machining,the influence of different process parameters(pulse voltage,pulse frequency and grinding wheel feed speed)on the hole quality was studied.The process parameters were optimized.When the combination voltage of the parameters was 4V,the frequency was 50KHz,the feed speed was 0.3mm/min,and the speed of the grinding wheel was 10000r/min,the micro holes with high quality were machined.Taking the residual stress of machined surface as an index,the superiority of electrolytic grinding to reduce the residual stress of machined surface is verified.