The Variation Of Wire Impedance And Experimental Research During Wire Exploding Spray Coating Process

Wire exploding spray coating(WESC) technology is more capable than other spray methods to complete hard tasks,such as material inner surface modification,fast spray.The research on WESC have an urgent demand by productive activity.The detailed research contents in this paper are listed below.The development WESC device.Based on the understanding of the WESC process,the following parts of the WESC device are mainly researched,namely,the trigger circuit for spark gap switch,voltage divider for pulsed voltage measurement,the Rogowski Coil for pulsed current measurement.10 kV～30 kV,sub-microseconds pulsed voltage can be generated by the WESC device,and 30 kV,100 kA pulsed voltage and current can be measured by the measurement device.The Electro-Magnetic Compatibility(EMC) of the device is emphasized in the research,and a series of EMC design is under taken to ensure the steady and reliable operating of the device,and also to improve the accuracy of the measurement device.The variation of the wire impedance and correlated parameters during WESC process is in-depth researched.The F.D.Bennett and A.Hobson wire impedance models and their disadvantages are analyzed.The variation of the wire impedance is researched by both experimental and theoretical methods,which concluded as follows:the technical parameters,such as the initial capacitor voltage,circuit inductance,the diameter and length of wire,influence the variation of the wire impedance,also determine the mean maximum wire impedance,and finally affect the gasification rate of wire and the mean diameter of the metal micro-particles during wire exploding.Based on the study about the variation of wire electrical parameters,the model of maximum impedance which clarified the relationship between the technical parameters and the maximum impedance is established.The WESC technology for nonmetal surface modification is experimentally researched.WESC technology is used in preparing metal coating on nonmetal surface,such as glass,ceramic.It is confirmed that the WESC technology is suitable to prepare metal coating on nonmetal surface.A 0.2μm mean partieal diameter,18.37 kΩ^-1m^-1 electrical conductivity,and 2.63 MPa adhesive strength electrically conducting coating will be prepared under certain technical parameters are chosen,such as 20 kV initial capacitor voltage,3.9μH circuit inductance,and 0.3 mm diameter,12 cm length copper wire.The WESC technology is also doing a good job on the inner surface of the cylinder.Above all,the electricalprocess and physiealprocess of the WESC are closely integrated; the variation of wire impedance and other parameters are researched.And the research of the mechanism during WESC process is used to guide the selection of the technical parameters for a better coating effect.The preparation of metal coating on nonmetal surface by WESC is also researohed.