Study On The Vulnerability Of Armor Protection Of Infantry Fighting Vehicles By Energy-containing Fragments

Energy-containing fragments,also known as active fragments,is a new concept of destruction element that combines multifunctional energy-containing structural materials with prefabricated fragment.When the energy-containing fragment impact the target at high speed,it can produce chemical reaction,emits heat no less than explosive level,and ignite flammable and explosive components after penetrating the target,which can effectively improve the fragmentation damage efficiency and damage after effect,and enhance the damage power of light armored vehicles,radar and missiles and other targets,can be widely used in various types of shells,missiles and rockets fragment warhead.Its energy output mode is mainly kinetic energy penetration and high temperature heat,so the energy-containing fragments have better damage effect on fuel tank targets and electronic equipment.This paper analyzes the protection performance of domestic and foreign infantry fighting vehicles by collecting literature,selects a typical foreign light infantry fighting vehicle as the research object,establishes the equivalent model of armor protection and the equivalent target of vulnerable parts according to its functional structure composition,and determines the destruction criterion of parts under the action of energy-containing fragments.Theoretical analysis of the action mechanism of energy-containing fragments is carried out,and the process of fragments through the target is divided into three stages: impact initiation,target penetration and deflagration reaction,and the calculation of plastic deformation temperature rise and impact temperature rise generated by the extrusion of energy-containing fragments is elaborated,and the reaction mechanism of two typical energy-containing fragments commonly used is analyzed.On this basis,the ballistic limit of energy-containing fragments penetrating armor steel is simulated by numerical simulation using LS-DYNA software,and the influence of target plate thickness on fragment penetration is analyzed.Based on the SPH algorithm,the influence of target parameters on the distribution of debris clouds after the penetration of energy-containing fragments was further investigated.Finally,by conducting experimental verification,the penetration effect of energy-containing fragments on armor steel,the damage effect on aftereffect target and the ignition enhancement effect are studied,and the experimental results are compared with the numerical simulation to verify the validity of the numerical simulation.The test results show that the ballistic limits of （?）11mm,8.5g tungsten-zirconium alloy fragment penetrating 6mm and 12 mm armor steel are 586m/s and 850m/s respectively;the ballistic limit of （?）12×15mm,5.2g Al/PTFE fragment penetrating 6mm armor steel is 1192m/s;and both energy-containing fragments can cause structural damage to aftereffect targets after penetrating the armor steel.The tungsten-zirconium alloy fragment can develop a temperature of 87-539℃ after penetrating the armor steel,and the Al/PTFE fragment can develop a temperature of 175-1384℃,which has a good ignition effect on the flammable material behind the target.Combined with numerical simulation and experimental research,under the appropriate target speed and target angle,the energetic fragments are more likely to damage the weak parts of the armor protection of the light infantry fighting vehicle.Besides,it can break through the armor protection and damage the internal personnel and instruments by relying on the residual kinetic energy and deflagration reaction.