Cushion Materials Performance Test Of Projectile’s High-Velocity Penetration And Study On Its Dynamics Behavior

Projectile’s fuse may endure overload and harsh working environment in thehigh-velocity penetration process. Therefore, cushioning materials are required toprotect the fuse in the penetration. This paper employs a combination of experimentaland simulated method to study the mechanical properties and cushioning properties ofTeflon and aluminum foam under static and dynamic conditions, to establish theconstitutive equation of foam aluminum with small diameter and high porosity, and tostudy and simulate the projectile’s high-velocity penetration behavior under theconditions of presence or not of cushioning materials. The main contents are asfollows:First of all, the author of this paper conducts a research on mechanical propertiesand heat absorption properties of PTEE and aluminum foam which have differentporosity, and then analyzes the influences of porosity on the material properties ofaluminum foam. The results show that aluminum foam’s heat absorption performanceis superior to PTFE’s by contrasting PTFE and aluminum foam’s heat absorptionperformance, and it’s resistance to compression declines obviously when thetemperature rises. Temperatures crease and porosity decrease have the same effect.After observing the change of unit cell structure in the compression process, the authorstudies the compression deformation mechanism of aluminum foam and finds itcollapses layer-by-layer.Based on the experiment and simulation, with the references of previous studieson aluminum foam constitutive relations and considering the effect of the strain, strainrate, the relative density and temperature, the author puts forward constitutive equationof aluminum foam material in a certain density range, combining with the existingexperimental results to verify the reliability of constitutive equation.The author of this paper establishes three single-cell model of closed-cellaluminum foams, simple cubic model, face-centered cubic model and body-centered cubic model. DEFORM-3D software is employed to simulate the compression process.The result shows that face-centered cubic model is superior to simple cubic model andbody-centered cubic model. Subsequently, the compressive behavior of closed-cell aluminum foam with different porosity and apertures are simulated. It’s found thatporosity and aperture have greater influence on mechanical property. With the increaseof porosity, the elastic modulus and yield strength decrease. With the decrease ofaperture, plastic platform stage increased, elastic modulus and yield strength weresignificantly improved. Because of large errors existing between the simulation resultsand the experimental results of face-centered cubic model, C language combining withmodeling software is employed to build geometric model of closed-cell aluminumfoam with three-dimensional random ball model whose porosity, aperture and hole-wall could be adjusted.Finally, the behavior of penetration of multi-layered concrete targets of high-velocity projectile is studied by numerical simulation. The projectile withoutaluminum foam cushioning materials may cause damages to fuse so that it cannotwork due to overload acceleration. Therefore, we need to add cushioning material toprotect the fuse. The constitutive equation of aluminum foam is applied to numericalsimulation of projectile penetrating with cushioning material into multi-layeredconcrete targets. While the peak of acceleration can be greatly reduced in the projectilewith aluminum foam cushioning materials, which can well protect the fuse.