TY - JOUR
T1 - Quasi-static and dynamic deformation mechanisms interpreted by microstructural evolution in TWinning Induced Plasticity (TWIP) steel
AU - Park, Jaeyeong
AU - Kang, Minju
AU - Sohn, Seok S
AU - Kim, Sang Heon
AU - Kim, Hyoung Seop
AU - Kim, Nack J.
AU - Lee, Sunghak
PY - 2017/1/27
Y1 - 2017/1/27
N2 - As automotive steels require high impact resistance for absorbing impact energy upon vehicle body collision, detailed investigation of dynamic deformation behavior of TWinning Induced Plasticity (TWIP) steels is essentially needed. Here we show a plausible explanation of improving dynamic tensile properties by investigating deformation mechanisms using transmission electron microscopy and electron back-scatter diffraction analyses of interrupted tensile specimens. According to microstructural evolution results, slip mechanisms change from wavy slip to (planar+wavy) slip with increasing strain rate. With respect to twinning, the transition occurs from stacking faults to primary twins with increasing strain under quasi-static loading, while twinning becomes more activated under dynamic loading. Due to favorable effects of increased planar slip and twinning on tensile properties, the TWIP steel shows higher strength and similar ductility under dynamic loading. Our results demonstrate desirable applications of the TWIP steel to automotive steel sheets demanding excellent safety requirement of vehicle body.
AB - As automotive steels require high impact resistance for absorbing impact energy upon vehicle body collision, detailed investigation of dynamic deformation behavior of TWinning Induced Plasticity (TWIP) steels is essentially needed. Here we show a plausible explanation of improving dynamic tensile properties by investigating deformation mechanisms using transmission electron microscopy and electron back-scatter diffraction analyses of interrupted tensile specimens. According to microstructural evolution results, slip mechanisms change from wavy slip to (planar+wavy) slip with increasing strain rate. With respect to twinning, the transition occurs from stacking faults to primary twins with increasing strain under quasi-static loading, while twinning becomes more activated under dynamic loading. Due to favorable effects of increased planar slip and twinning on tensile properties, the TWIP steel shows higher strength and similar ductility under dynamic loading. Our results demonstrate desirable applications of the TWIP steel to automotive steel sheets demanding excellent safety requirement of vehicle body.
KW - Dynamic tensile test
KW - Planar slip
KW - Split Hopkinson tensile bar
KW - Twinning
KW - TWinning Induced Plasticity (TWIP) steel
UR - http://www.scopus.com/inward/record.url?scp=85003875645&partnerID=8YFLogxK
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U2 - 10.1016/j.msea.2016.12.037
DO - 10.1016/j.msea.2016.12.037
M3 - Article
AN - SCOPUS:85003875645
SN - 0921-5093
VL - 684
SP - 54
EP - 63
JO - Materials Science & Engineering A: Structural Materials: Properties, Microstructure and Processing
JF - Materials Science & Engineering A: Structural Materials: Properties, Microstructure and Processing
ER -