Enhancement of ballistic performance enabled by boron-doping in subzero-treated (ferrite+austenite+martensite) triplex lightweight steel

Dae Woong Kim, Selim Kim, Junha Yang, Sunghak Lee, Seok Su Sohn

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)


Investigations of dynamic deformation and ballistic performance of ultra-high-strength lightweight steels for steel armor applications have not been conducted to date. In this study, effects of boron(B)-doping on ballistic performance were explored in subzero-treated Fe-0.3C-9Mn-5Al and Fe-0.3C-9Mn-5Al-0.005B (wt%) lightweight steels in relation to band structures and B segregation. The dynamic deformation and adiabatic shear band (ASB) formation behaviors were examined by a Hopkinson pressure bar (SHPB). The band structure is critical in inhibiting ASB propagation, as it is continuously blocked at tempered-martensite/ferrite boundaries. The crack propagates along the embrittled ASB and penetrates into tempered-martensite/ferrite boundaries, producing delamination of elongated grains in the undoped steel. On the other hand, the delamination does not occur in the B-doped steel because the segregation of solute B at prior austenite grain boundaries enhances the grain-boundary cohesion. Thus, the B-doped steel outperforms conventional rolled homogeneous armor steels and the undoped steel as well, providing a significant deal of potential for developing excellent ballistic-performance lightweight steel armors.

Original languageEnglish
Article number112021
JournalMaterials Characterization
Publication statusPublished - 2022 Aug

Bibliographical note

Funding Information:
This work was supported by the Korea Institute for Advancement of Technology (KIAT) grant funded by the Korea Government (MOTIE) ( P0002019 , The Competency Development Program for Industry Specialist), and the Korea University Grant (Dr. Seok Su Sohn).

Publisher Copyright:
© 2022 Elsevier Inc.


  • Adiabatic shear band (ASB)
  • Ballistic performance
  • Boron-doping
  • Medium-Mn lightweight steel
  • Split Hopkinson pressure bar (SHPB)

ASJC Scopus subject areas

  • General Materials Science
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering


Dive into the research topics of 'Enhancement of ballistic performance enabled by boron-doping in subzero-treated (ferrite+austenite+martensite) triplex lightweight steel'. Together they form a unique fingerprint.

Cite this