Caracterização físico-química e avaliação de sistemas de proteção contra corrosão de projéteis deflagrados por armas de fogo

Abstract


It is commonly observed in ballistics testing laboratories that the integrity of firearm projectiles to be analyzed is irreversibly damaged, which makes the bullet comparison tests difficult or even unachievable. The scientific literature on different forms of bullets protection against corrosion and storage is in general scarce and difficult to access because those procedures are not published in literature. In the present work, three different types of projectiles expelled from firearms with rifled barrels were characterized by Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectrometry (EDX) and X-Ray Diffraction (XRD), and it was analyzed the effect of coating such projectiles with anticorrosive lubricant (WD) and paraffin (PA) in increasing resistance to oxidation/corrosion and in preserving the bullets fingerprints. The corrosion analysis was carried out by comparing the rifling marks before and after the projectiles coating by submitting them to a forced oxidation testing. The results obtained so far suggest that paraffin coating remains for more time compared to the WD coating. Nevertheless, both materials require a simplified low-cost methodology for preserving projectiles expelled from firearms for more than 33 days.

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