Experimental Study On Electrochemical Machining Of Silicon Carbide Reinforced Aluminum Matrix Composites

Silicon carbide reinforced aluminum matrix composites has excellent properties such as high specific strength,specific stiffness and hardness,and low mass density.They are widely used in many fields such as aviation flight,optical special precision instruments,and automotive electronics.However,due to the strengthening effect of the reinforcement,the stress distribution around the reinforcement particles is uneven and plastic deformation does not occur.Therefore,using traditional processing methods to process them will cause violent tool wear,and indirectly cause low processing efficiency and surface quality.Electrochemical machining perfectly circumvents the above-mentioned problems in traditional machining.It also has the characteristics of removal rate,which is not affected by the physical properties of the material and good processing surface quality.Currently there is few of researcher focuses on experimental rules of chemical processing,so this article conducts experimental research on them.The main contents of this research are as follows:1)Analysis of material removal mechanism during electrochemical machining of silicon carbide reinforced aluminum matrix composites section consists,the electrochemical dissolution of the main aluminum matrix and the silicon carbide reinforced aluminum matrix composite material,the formation and cracking of the oxide film on the matrix surface,and the removal of silicon carbide particles.During study various factors are analyzed that affect electrochemical machining from the electrolyte,the flow field of the machining gap,and the electric field The determination of the most influencing factors is done to lay a theoretical foundation for the experimental research of electrochemical machining.2)Analysis and research on the electrochemical dissolution characteristics of silicon carbide reinforced aluminum matrix composites section consists,the study on polarization characteristics and anodic polarization curves of silicon carbide reinforced aluminum-based composites.The study is performed in sodium chloride,sodium nitrate,and sodium sulfate electrolytes,with mass concentrations of 5%,10%,15%,and 20%.These chlorine sodium nitrate electrolytes have strong activity and high current density.Both sodium nitrate and sodium sulfate have a passivation interval,while sodium sulfate has the lowest current density,thus,sodium nitrate is used as the main electrolyte.In order to improve the electrochemical processing rate,the sodium chloride is compounded in the main electrolyte of sodium nitrate.By comparing the current density and the passivation interval,the specific formula of the electrolyte that guarantees the passivation area and increases current density,which finally obtain 10%NaN03+2%NaCL?3)The regularity experiment of the influencing factors of the electrochemical machining of silicon carbide reinforced aluminum matrix composites section consist,the determination of reasonable range of processing voltage,processing frequency,duty cycle,and processing spacing through single-factor experiments.The influencing range is determined by studying the influence of these parameters on the surface roughness of the material and the material removal rate.In order to study the pairing of materials experiment,which was designed and analyzed,using "Box-Behnken" response surface method.The material surface roughness and the removal rate were obtained,and the significance analysis of the influencing factors was carried out through binary fitting of the experimental results.The mathematical model and the significance level of each factor,and then the mathematical model is predicted and verified.The minimum surface roughness of the material is obtained under the processing voltage of 7V,the processing frequency of 1638Hz,the duty cycle of 30.5%,and the processing distance of 0.38mm.The roughness is 4.4um,the maximum removal rate of the material is 0.56mg/s when the processing voltage is 13.76V,the processing frequency is 1975Hz,the duty cycle is 68.5%,and the processing distance is 0.418mm.In order to optimize the surface roughness and material removal rate,a genetic algorithm multi-objective optimization solution was made,and the material surface was obtained at a processing voltage of 7.82V,a processing frequency of 1970.4Hz,a duty cycle of 34.7%,and a processing distance of 0.344mm.The roughness is 4.69um,and the material removal rate is 0.303mg/s.