Мікроструктурні зміни високоміцної сталі Fe-26Mn-10Al-1.2Si-2.2Cr-1.8Ni-0.15V-1C після балістичного ураження

• Date: 2025
• Main Authors: Voron, M. М., Tymoshenko, A. M., Semenko, A. Yu., Smirnov, O. M., Schwab, S. L., Skorobagatko, Yu. P.
• Format: Article
• Published: Physico- Technological Institute of Metals and Alloys of the NAS of Ukraine 2025
• Subjects: Fe-Mn-Al-C; броньова пластина; балістичне ураження; зміни мікроструктури; мікродефекти; розподіл навантаження
• Online Access: https://momjournal.org.ua/index.php/mom/article/view/2025-3-1
• Journal Title: Metal Science and Treatment of Metals

The manuscript is devoted to the study of structural changes in the penetration zone of Fe-26Mn-10Al-1.2Si-2.2Cr-1.8Ni-0.15V-1C steel, which was developed for ballistic damage protection. Obtaining thin plates from lightweight high-strength steels based on the Fe-Mn-Al-C system for such use is an extremely promising and unexplored task. The work analyzes the influence of mechanical properties and mechanisms of microstructural changes, according to which armor metallic materials and studied type steels can resist bullet damage most effectively. To provide the research, as-cast steel billet was obtained under conditions of open induction melting, and then it was subsequently subjected to hot plastic deformation and normalization. The resulting plate was ballistic tested and the structure of the near-bullet hollow area was investigated. Studies of mechanical properties revealed extremely high strength of steel, the required level of plasticity and average hardness: UTS=2240 MPa, YS=1784 MPa, δ=6.2%, ψ=16.8%, HRC=42-46. Studies of the bullet hollow cross-section area showed the formation of two zones. The first zone repeated the shaper of the bullet and demonstrated significant local plastic deformation of the steel near the strike surface. In the near-surface region, local recrystallization and a microhardness decrease was observed due to thermal influence. When moving closer to the central zone, surface hardening is observed, which is expressed in a noticeable increase in microhardness. The second zone shows signs of brittle fracture. In its microstructure, adiabatic shear bands and places of stress accumulation that form microcracks are observed. In the zone of l plate failure, the formation of microdefects coalescence areas was detected, the shape of which repeats the load distribution inside the material. The obtained data indicate that the proposed steel is suitable for protection against ballistic damage, but at greater thicknesses. It is able to resist ballistic loads due to the effective absorption of impact energy, which is expressed in the implementation of several mechanisms simultaneously - local hardening, formation of ASB, accumulation of defects and stresses and the sequential formation of microcracks, as well as in their coalescence during the deformation of the material.