Projectile

About: Projectile is a research topic. Over the lifetime, 13047 publications have been published within this topic receiving 115563 citations.

High-temperature high-velocity impact on honeycomb sandwich panels

Abstract: This work presents an investigation on the damage and high-speed impact deformation mechanisms at elevated temperatures in honeycomb sandwich panels made from PM1000 and PM2000 alloys. The impact temperatures ranged from 22 °C to 866 °C. The investigation was performed experimentally using a custom-made gas gun rig, and by using Finite Element and developing a phenomenological analytical model to predict the residual velocity and ballistic limit equations for the case in which the diameter of the projectile is close or smaller to the honeycomb cell length. The sizes of the holes have been also evaluated by carrying out numerical thermal loading simulations on honeycomb sandwich specimen models impacted at high speed. The predictions provided by the Finite Elements and the analytical model give a good agreement with the results from the experimental tests. The hole diameters for the two idealized normal impact cases, in which the projectile hits the cell core and at the triple-wall intersection of the core, were also presented as a function of the projectile diameter and velocity in this paper.

Cross sections for the production of highly charged argon and xenon recoil ions in collisions with high-velocity uranium projectiles

Abstract: Cross sections for the production of recoil ions were measured for collisions of highly charged Un+ (n approximately=65-75) projectile ions with argon and xenon as a function of the projectile velocity (3.6-15.5 MeV u-1) and the final charge states of both collision partners. A recoil-ion-projectile-ion coincidence technique made it possible to distinguish between pure ionisation of the target and ionisation of the target plus capture of one or more electrons into bound state of the projectile (CI). It was found that hydrogen-like and bare argon ions are most efficiently produced at the highest velocity investigated by pure ionisation with cross sections that exceed 10-18 cm2. Highly charged xenon ions, however, are also most effectively created at the highest velocity but via the CI reaction channel.

Strain-Rate Effects in Replica Scale Model Penetration Experiments

Abstract: : A computational study has been performed to quantify the effects of strain rate on replica-model (scaled) experiments of penetration and perforation. The impact of a tungsten-alloy long-rod projectile into an armor steel target at 1.5 km/s was investigated. It was found that over a scale factor of 10, strain-rate effects change the depth of penetration, for semi-infinite targets, and the residual velocity and length of the projectile, for finite- thickness targets, on the order of 5%. Although not modeled explicitly in the present study, the time-dependence of damage was examined. Damage accumulation is a strong function of absolute time, not scaled time. At homologous times, a smaller scale will have less accumulated damage than a larger scale; therefore, the smaller scale will appear stronger, particularly in situations where the details of damage evolution are important.

Ballistic Impact Behaviour of a Tempered Bainitic Steel Against 7.62 mm Armour Piercing Projectile

Abstract: In this study, occurence of failure after the interaction between an armour piercing 7.62 mm caliber projectile and a tempered bainitic steel has been investigated. The shot was performed at zero degree with a projectile velocity of 840 m/s. After the shot, microstructural and fractographical examinations were carried out on the sample taken from the perforated region. In the etched sample, it was observed that the morphology of the original microstructure had changed and adiabatic shear bands (ASBs) were formed in regions close to the direction of penetration. Main failure is ductile (plastic) deformation was followed by cleavage after shot. Cracks due to adiabatic shear band and formation of abrasive wear were seen. The perforation mode of the steel was a typical petalling.