Preparation Of SiC Ceramic Composite Armor And Ballistic Performance Analysis And Verification

SiC ceramic materials are widely used in aerospace,national defense and military industry because of their excellent properties such as high strength,high hardness,wear resistance and so on.In order to adapt to the modern wars and improve the battlefield adaptability of individual protective equipment,this paper focuses on the lightweight of individual armor and reduces the area density of armor under the premise of ensuring bulletproof performance.Using reactive sintering SiC ceramics as front panel and ultra-high molecular weight polyethylene（UHMWPE）laminate as back plate,polyurea and Si O₂ aerogel were added as buffer layer innovatively.The bulletproof properties of composite plates with different structures were calculated by finite element method（FEM）,and the bulletproof performance and damage mechanism were analyzed.The III grade composite armor with light weight and can protect 7.62mm armor-piercing bullet was prepared.The test results of bulletproof performance of composite armor show that the addition of buffer layer can effectively reduce the surface density,but there are still some problems such as large bulging of back plate,which may cause damage to human body,which need to be further studied and solved.In the research of finite element calculation,LS-DYNA advanced FEM calculation software is used to calculate the bulletproof performance of ceramic/UHMWPE composite armor with different structures based on Lagrange algorithm.The constitutive model of ceramic material is Johnson-Holmquist model based on strength,pressure and damage model,the constitutive model of UHMWPE laminated plate is Composite-Damage constitutive model based on chang-chang composite model,the constitutive model of buffer layer material is Mooney-Rivlin constitutive model to simulate nonlinear elastic material,and the constitutive model of metal material is Johnson-Cook constitutive model under the condition of large strain and high strain rate,which is combined with Gruneisen equation of state.According to the results of FEM calculation,the damage mechanism of ceramic includes crushing damage,ceramic broken cone and crack propagation,the damage mechanism of ultra-high molecular weight polyethylene back plate includes perforation damage,shearing damage,peeling damage and tensile damage,and the failure mode of ceramic/UHMWPE composite armor includes invasive failure,penetration failure and jet failure.For different panel ceramic materials,SiC has more advantages when the composite insert board prevents high speed bullets.The Ⅲ grade composite armor with buffer layer was prepared and the bulletproof performance was tested.The ceramic panel is formed by grouting and reactive sintering of SiC ceramics.This molding process can ensure the structure and composition uniformity of the ceramics,reduce the density and improve the hardness and fracture toughness of the ceramics,so that they have good impact resistance.According to the test results of the bulletproof performance of the composite insert board,it can be seen that the limit velocity of the composite insert plate is 850 m/s under the reference surface density AD=31kg/m²,when the composite armor is used to prevent 7.62mm armor-piercing bullet,and the composite armor fails during the bulletproof process.For buffer layer materials,polyurea is beneficial to the thinning of armor thickness,while Si O₂ aerogel is more beneficial to armor weight loss.By using reactive sintering SiC panel,the average surface density and average weight of the composite armor with buffer layer material are reduced by 37.5%and 1.02 kg,respectively,which is beneficial to the lightweight of armor.