Analysis And Study Of Thermal Ablation Behavior Of Gun Barrel

As the main firepower output weapon widely used in modern warfare,artillery plays an irreplaceable role in the armies of all countries in the world.As the most critical component of the gun,the life of the barrel determines the combat capability of the gun,but because with the improvement of the power of the gun,the service environment of the barrel of the gun is becoming more and more harsh,and under the action of high temperature and high pressure,it will lead to serious ablation and wear of the bore of the barrel,which greatly reduces the life of the barrel and affects the performance of the gun.Therefore,in order to extend the service life of the gun barrel,exploring the ablation and wear mechanism of the gun body tube has become a hot spot for scholars from all over the world.In this paper,the wear simulation experiment of the inner wall of the body tube is established by the high-temperature and high-speed friction and wear machine,and the friction coefficient of the sample under different loads and the friction effect of copper materials on the gun steel are tested.A long pulse width laser was used to simulate the thermal ablation behavior of the body tube to test the ablation characteristics of the sample under different pulse energies.Through the simulated ablation experiment of gunpowder gas washout,the ablation law of gunpowder gas samples under gunpowder gas erosion was analyzed.The wear and ablation mechanism of samples is studied by technical means such as SEM,XRD and EDS.(1)The friction coefficient of the gun steel specimen under different loads shows a trend of rising first and then decreasing,and the friction curve is the most stable when the load is 100 N.During the friction process,the copper on the friction pair is transferred,attached to the surface of the gun steel matrix,and oxidation occurs,and with the increase of load,the copper penetrates deep into the gun steel matrix from the surface.At a load of 150 N,the recrystallized spherical substance after melting of the matrix was found on the surface of the gun steel matrix,and the C element content of the spherical substance far exceeded that of the gun steel matrix.(2)In the laser ablation experiment,the ablation morphology of the surface of the cannon steel specimen is mainly cracked cracks and block peeling,and the peeling phenomenon is more serious with the increase of laser energy.The molten matrix peels form an ablation pit and form a multilayer oxide dominated by Fe around the ablation pit.(3)After being washed by gunpowder gas,oxidation and carburizing occurred on the surface of the gun steel sample,and deeper and longer cracks appeared in the area where the surface of the sample was more seriously oxidized.At the cross-section,the white layer formed by the ablation of gunpowder was observed,and multiple longitudinal cracks perpendicular to the interface appeared in the white layer at the positive line,more gunpowder gas residues were found at the black line,and part of the Cl element diffused to the inside of the matrix.The cross-sectional microstructure of the body tube specimen can be divided into three regions from the surface to the inside,namely the hardening area,the transition zone,and the matrix area.