Recent technological advances have expanded the use of 3D-printed polymer components across industries, including a growing interest in military applications. The effective defensive use of such materials depends on a thorough understanding of polymer properties, printing techniques, structural design, and influencing parameters. This paper analyzes the ballistic resistance of 3D-printed polymer structures against 9 × 19 mm projectiles. Cuboid targets with different infill patterns—cubic, grid, honeycomb, and gyroid—were fabricated and tested experimentally using live ammunition. Post-impact, CT scans were used to non-destructively measure projectile penetration depths. The honeycomb infill demonstrated superior bullet-stopping performance. Additionally, mechanical properties were experimentally determined and applied in FEM simulations, confirming the ability of commercial software to predict projectile–target interaction in complex geometries. A simplified analytical model also produced satisfactory agreement with experimental observations. The results contribute to a better understanding of impact behavior in 3D-printed polymer structures, supporting their potential application in defense systems.

Constant development of protective materials and armored systems requires continuous improvements in the field of anti-tank ammunition development. One of the most commonly used anti-tank explosive ordnance are shaped charge projectiles/warheads. Serbia has been globally recognized for decades in the production of high-quality hand-held rocket launchers equipped with various calibers of shaped charge ammunition. One of the most famous representatives is the 64 mm hand-held rocket launcher, better known as "Zolja". Although it has been in use for decades and it has insufficient capabilities against more modern protection systems, retaining the traditional design and long-established production technologies, along with the use of more potent and modern explosives, could significantly enhance its penetration power. This paper uses analytical calculation and numerical simulation to analyze how different explosive materials affect the velocity of shaped charge jet of 64 mm M80 warhead, which ultimately directly impacts its penetration capabilities.

The objective of this paper was to create an economical and abecedarian 3D printing method for the production of solid microneedles, as a more efficient transdermal drug delivery method, for day-to-day use in companion animals. The process of 3D printing was conducted using two types of 3D printers, utilizing the FDM and SLA printing techniques. Modulus of Elasticity was calculated for the determination of mechanical properties of the material, wherethe printed specimen was subjected to axial loading, and deformations were measured using an optical scanner. Post-processing was conducted by washing microneedles in isopropyl alcohol, followed by UV curing. The procedure of testing penetration capabilities was conducted at two sites of cat skin: Auris externa and the lateral part of the abdomen. The SLA printing method was more precise, resulting in higher quality microneedles for animal use compared to the FDM printing technique. Modulus of Elasticity was calculated and the value E=0.9 GPa can be used. Testing proved that the printed model was able to penetrate the skin at the tested sites. The use of microneedles is simple and economical, and therefore has wide applications in small animal practice. Veterinarians can access microneedle design repositories and print them for more effective transdermal drug delivery. The multifunctionality and transferability of the design in the present study ensure that it can be further modified to provide personalized therapy.