Study On Sliding Arc Ablation Mechanism And Armature Motion Characteristics Of Copper Alloy Of Linear Propulsion Mechanism

With the continuous innovation of science and technology,the replacement of military weapons is getting faster and faster.Electromagnetic emission technology uses electromagnetic force instead of gunpowder to launch objects and kills and destroys targets with ultra-high kinetic energy,which is a new concept weapon technology that all military powers in the world are competing to develop.As the main body of electromagnetic energy to mechanical energy conversion,electromagnetic emitting devices will face many problems in practical work and have always been the focus of research.When the electromagnetic railgun is launched,it enters MJ-level electric energy,and the export speed reaches several kilometers per second,its working conditions are extremely harsh,and the material is subjected to great instantaneous current impact,which is easy to cause serious ablation of the track.Studies have shown that the ablation on the surface of the orbital electrode through which the projectile passes is more serious.Therefore,revealing the sliding arc ablation mechanism and armature motion characteristics of copper alloy of linear propulsion mechanism under extreme environment is of great significance for improving the service life of linear propulsion mechanism.To study the influence of initial contact pressure on the sliding arc ablation characteristics and armature motion characteristics of copper alloy of linear propulsion mechanism,combined with the characteristics of armature mass loss,guide rail surface ablation,armature outlet speed and other characteristics under actual contact pressure,an electromagnetic emission experimental platform with adjustable initial contact pressure is designed.The platform can apply different initial contact pressures,which can well control the size of the contact pressure and measure the size of the contact pressure within the controllable range of error.The experimental device built can accurately measure the output speed of the armature and the mass loss of the armature and obtain the surface damage of the armature and guide rail,so the experimental platform has perfect functions and can meet the needs of research.The experimental results show that under the same capacitor discharge energy,the initial position contact pressure is increased,and the emission speed gradually increases with the increase of the initial contact pressure,the mass loss of the armature is gradually reduced,and the damage of the guide rail is gradually reduced,but the excessive initial position contact pressure inhibits the emission speed.Therefore,in practical applications,it is necessary to provide an optimal contact pressure for each transmission voltage,to achieve the purpose of small ablation damage and emission speed up to standard.Under the same contact pressure,the emission energy is increased,and the armature emission speed is significantly increased,but the damage to the armature and orbit is also increasing.Therefore,it is not possible to blindly increase the capacitor discharge energy without changing the initial contact pressure to achieve the purpose of increasing the emission speed,otherwise the side will cause great damage to the guide rail and armature and reduce the service life of the guide rail.In addition,the number of launches is an important indicator to measure the service life of the linear propulsion mechanism,for the influence of different initial contact pressure on the number of launches,the experiment of the cumulative effect of the linear propulsion mechanism is carried out,the experimental results show that the aluminum of the armature is attached to the surface of the copper alloy guide rail after launch under the same initial contact pressure,with the increase of the number of launches,the aluminum attached to the guide rail will continue to thicken,so that the friction between the armature and the guide rail gradually increases,and finally the exit speed of the armature decreases.And with the increase in the number of launches,the rate of speed decline continues to increase;Different initial contact pressures also affect the number of launches of the rail,and it is necessary to find the initial contact pressure that satisfies the maximum number of launches at the launch outlet speed.In summary,different initial contact pressures have a great influence on the sliding arc ablation characteristics and armature motion characteristics of the copper alloy of the linear propulsion mechanism under extreme environments.Exploring the influence of different initial contact pressures on the linear propulsion mechanism is of great significance for improving the service life of the linear propulsion mechanism and has important reference significance for the design and manufacture of the linear propulsion mechanism.