| Nowadays,the processing technology of conductors and semiconductors is very mature,but the processing of non-conductors is still being explored.Non-conductor ceramic materials are widely used in important fields such as aerospace,national defense,and biochips.For example,air film holes in thermal barrier coatings of aero generator turbine blades,applications of microfluidic chips,quartz resonators and biochips.However,this material has the characteristics of high melting point,hardness and brittleness,so it is not easy to process.Spark Assisted Chemical Engraving(SACE)is a processing method suitable for processing non-conductor materials.This method is expected to realize damage-free processing at the micro-scale due to the physical and chemical etching process at the same time.However,this processing method still needs to be improved.There are many environmental variables and influencing factors during processing,including: immersion depth,electrode shape,electrolyte concentration,spindle control method,etc.This article aims to study the spindle control strategy,and then optimize the efficiency and accuracy of SACE machining.This thesis firstly faces the SACE machining of ?0.5mm hollow tool electrode,and proposes a spindle control model of the hollow punching fluid pressure feedback machining gap.From a theoretical point of view,the theoretical model of hollow electrode flushing is analyzed in two parts: the liquid cavity part of the hollow electrode cylindrical tube and the machining gap part of the hollow electrode end acting on the surface of the workpiece.Using resolution,accuracy,and response rate as evaluation indicators qualitatively,the law of inlet pressure feedback processing gap size is analyzed.Through Comsol software modeling and simulation,the corresponding relationship of the hollow punching hydraulic pressure under the condition of 1-40?m machining gap is discussed,and the feasibility of the model is analyzed for the electrode tilt problem.Furthermore,considering the SACE machining of a ? 0.1mm micro-solid tool electrode,the elastic feed control method of the micro contact force feedback between the tool electrode and the workpiece surface was studied,and the performance test of the elastic feed force feedback spindle based on the flexible hinge was carried out,and the feedback was achieved.The two spindle control strategies of fixed feed depth and constant contact force feedback have been verified by process experiments to verify the feasibility and effectiveness.The focus is on the relationship between the contact force and the electrode position of the spindle control tool,and the influence of the scanning speed and scanning method on the processing effect is tested.The process experiment optimizes the processing effect of the micro-groove,and obtains the controllable precision and influencing factors in the processing technology. |
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