Microstructural changes of high-strength steel Fe-26Mn-10Al-1.2Si-2.2Cr-1.8Ni-0.15V-1C after ballistic damage

Authors

DOI:

https://doi.org/10.15407/mom2025.03.003

Keywords:

Fe-Mn-Al-C, armor plate, ballistic damage, microstructure changes, microdefects, load sharing

Abstract

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.

References

Børvik T., Dey S. and Clausen A.H. Perforation resistance of five different high-strength steel plates subjected to small-arms projectiles. Intern. J. of Impact Engineering. 2009, vol. 36, no. 7, pp. 948–964. https://doi.org/10.1016/j.ijimpeng.2008.12.0032

Manganello S. J., Abbott K. H. Metallurgical Factors Affecting the Ballistic Behaviour of Steel Targets. J. Mat. 1972. Vol. 7. рp. 231–239.

V. I. Veis, A. Yu. Semenko. M. M. Voron, A. M. Tymoshenko R. F. Likhatskyi I. F. Likhatskyi, Zh.V.Parkhomchuk.(2025). Lightweight Fe-Mn-Al-C steels: current state, manufacturing and implementation prospects. Steel Res Int. 2025. 202400904. https://doi.org/10.1002/srin.202400904

Field, D. M., Limmer, K. R., Hornbuckle, B. C., Pierce, D. T., Moore, K. E., & Sebeck, K. M. (2022). Alloy Partitioning Effect on Strength and Toughness of κ-Carbide Strengthened Steels. Materials, 15(5), 1670. https://doi.org/10.3390/ma15051670

Smirnov O.M., Voron M.M., Tymoshenko A. M., Semenko A. Yu., Skorobagatko Yu. P., Schwab S.L. Effect of heat treatment on the structure of the Fe-28Mn-12Al-0.9Si-1.35C alloy, additionally dopped by Ni 3.3, Cr 1, V 0.15 (wt. %). VII international conference “Welding and related technologies”, 7-10 October, 2024, Yaremche, Ukraine. рр. 176-179. https://doi.org/10.1201/9781003518518-35

Chen, P., Li, X., & Yi, H. (2020). The κ-Carbides in Low-Density Fe-Mn-Al-C Steels: A Review on Their Structure, Precipitation and Deformation Mechanism. Metals, 10(8), 1021. https://doi.org/10.3390/met10081021

Królicka, A., & Caballero, F. G. (2025). B2-strengthened Fe-Mn-Al-C-Ni steels as a promising environmentally friendly structural material: review and perspectives. Critical Reviews in Solid State and Materials Sciences, 1–30. https://doi.org/10.1080/10408436.2025.2542362

Castañeda, J. A., Zambrano, O. A., Alcázar, G. A., Rodríguez, S. A., & Coronado, J. J. (2021). Stacking Fault Energy Determination in Fe-Mn-Al-C Austenitic Steels by X-ray Diffraction. Metals, 11(11), 1701. https://doi.org/10.3390/met11111701

Guan, X., Qu, S., Wang, H., Cao, G., Feng, A., & Chen, D. (2024). Adiabatic Shear Localization in Metallic Materials: Review. Materials, 17(21), 5365. https://doi.org/10.3390/ma17215365

Chen, S., Rana, R. (2021). Low-Density Steels. In: Rana, R. (eds) High-Performance Ferrous Alloys. Springer, Cham. https://doi.org/10.1007/978-3-030-53825-5_6

Bai, R., Du, Y., He, X., & Zhang, Y. (2024). The Influence of Cr Addition on the Microstructure and Mechanical Properties of Fe-25Mn-10Al-1.2C Lightweight Steel. Metals, 14(6), 687. https://doi.org/10.3390/met14060687

Jia, X., Gao, G., Gui, X., Feng, C., Misra, K., & Bai, B. (2024). Uncovering Microstructure–Property Relationship in Ni-Alloyed Fe–Mn–Al–C Low-Density Steel Treated by Hot-Rolling and Air-Cooling Process. Acta Metallurgica Sinica (English Letters), 37(4), 713–725. https://doi.org/10.1007/s40195-024-01666-4

Karantza, K. D., & Manolakos, D. E. (2023). A Review on the Adiabatic Shear Banding Mechanism in Metals and Alloys Considering Microstructural Characteristics, Morphology and Fracture. Metals, 13(12), 1988. https://doi.org/10.3390/met13121988

Published

2025-09-30

How to Cite

Voron M. М., Tymoshenko, A. M., Semenko, A. Y., Smirnov, O. M., Schwab, S. L., & Skorobagatko, Y. P. (2025). Microstructural changes of high-strength steel Fe-26Mn-10Al-1.2Si-2.2Cr-1.8Ni-0.15V-1C after ballistic damage. Scientific Technical Journal ‘’Metal Science and Treatment of Metals’’, 31(3). https://doi.org/10.15407/mom2025.03.003

Most read articles by the same author(s)