TY - JOUR
T1 - Enhancement of ballistic performance enabled by boron-doping in subzero-treated (ferrite+austenite+martensite) triplex lightweight steel
AU - Kim, Dae Woong
AU - Kim, Selim
AU - Yang, Junha
AU - Lee, Sunghak
AU - Sohn, Seok Su
N1 - 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.
PY - 2022/8
Y1 - 2022/8
N2 - 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.
AB - 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.
KW - Adiabatic shear band (ASB)
KW - Ballistic performance
KW - Boron-doping
KW - Medium-Mn lightweight steel
KW - Split Hopkinson pressure bar (SHPB)
UR - http://www.scopus.com/inward/record.url?scp=85131406782&partnerID=8YFLogxK
U2 - 10.1016/j.matchar.2022.112021
DO - 10.1016/j.matchar.2022.112021
M3 - Article
AN - SCOPUS:85131406782
SN - 1044-5803
VL - 190
JO - Materials Characterization
JF - Materials Characterization
M1 - 112021
ER -