System Design And Experimental Study Of Continuous Wire Electrical Explosion Spraying

In the process of modern industrial production,thermal spraying is the key technology to strengthen the surface properties of materials.As a new thermal spraying method,electrical explosion spraying has many outstanding advantages compared with traditional thermal spraying technology,such as high bonding strength between coating and substrate,small thermal impact on substrate,etc.At present,the research of electrical explosion spraying mainly focuses on the analysis of coating performance,the existing spraying equipment is not highly automated,and there is a lack of research on electrical explosion spraying for mass production.Based on this,a system for continuous electrical explosion spraying was developed.Based on this system,mechanism analysis and experimental research were combined to explore the mass production-oriented electrical explosion spraying method.Based on the theories and methods of pulse power technology,detection technology and automation equipment,a continuous wire electrical explosion spraying system was developed.The system is mainly composed of the high-voltage charging and discharging circuits,the continuous wire feeding subsystem and the spray gun operation subsystem.With the metal wire as the spraying material,the control mode of automatic wire feeding with wire carrier and non-contact large current introduction was proposed.The metal wire was continuously and automatically fed under the drive of the continuous wire feeding mechanism,and the metal wire and inner electrode of the spray gun were introduced with a large current through the air gap breakdown to achieve non-contact discharge.With PLC as the core,it can control the continuous automatic feeding of the carrier wire,the position adjustment of the spray gun,the high voltage charging and energy storage and the connection and disconnection of the discharge circuit to achieve continuous automatic electrical explosion,which provides an effective means for the efficient mass production of the coating.The development of the continuous wire electrical explosion spraying system provides a platform for experimental and theoretical research related to wire electrical explosion.Based on the change of resistivity of metal wire in solid-liquid-vapor and other physical states and the conductivity of air gap,combined with experiments,the65 Mn and 316 L wire electrical explosion impedance models were established,and the inherent distribution parameters of the device in the discharge circuit were analyzed,and the equivalent circuit model of the wire electrical explosion process was established.The PSpice software was used to simulate the discharge circuit,and the electrical characteristics of each part and the variation law of electrical parameters were deeply studied.The influence law of time-varying nonlinear electrical parameters on the wire electrical explosion process was investigated,which provides theoretical guidance for the subsequent experiment.Using the self-developed continuous wire electrical explosion spraying system,65 Mn and 316 L alloy wires as spraying materials,the wire electrical explosion spraying experiment was carried out.The voltage and current waveforms in the discharge circuit were collected.Combined with the analysis of wire electrical explosion mechanism,the influence of charging voltage and wire diameter on the deposition energy of wire and the coating quality were studied,and the high-quality coatings that meet the requirements of engineering application were obtained.On the basis of experimental research,further,the spraying process parameters were optimized.SVR,RF and XGBoost algorithms were used to establish the approximate model between the process parameters and the surface roughness and deposition rate of the coating.Based on RF approximation model with the best prediction effect,NSGA-Ⅱ algorithm was used for the multi-objective optimization of spraying parameters.RF-NSGA-Ⅱ based spraying parameter optimization model was established,and the optimal process parameter combination was obtained.The experimental results show that the RF-NSGA-Ⅱ model has a good optimization effect and high engineering practical application value,which provides a solution for the scientific and reasonable setting and optimization of wire electrical explosion spraying process parameters.