TY - JOUR
T1 - Effect of Ferrite/Martensite Phase Size on Tensile Behavior of Dual-Phase Steels with Nano-Precipitation of Vanadium Carbides
AU - Chandiran, Elango
AU - Sato, Yu
AU - Kamikawa, Naoya
AU - Miyamoto, Goro
AU - Furuhara, Tadashi
PY - 2019/9/15
Y1 - 2019/9/15
N2 - This study investigates the effect of ferrite/martensite phase size and dispersion of nano-precipitates in ferrite on strength, ductility, and fracture behavior of dual-phase (DP) steels. Dispersion of nano-precipitates in ferrite improves the strength with keeping sufficient uniform elongation and post-uniform elongation, while decrease in ferrite/martensite phase size has a little effect on the increase in strength in the phase size range investigated. However, the refinement of phase size significantly improves the post-uniform elongation and reduction in area. It is concluded therefore that a simultaneous combination of refinement of ferrite/martensite phase size and dispersion of nano-precipitation in ferrite is effective to significantly improve the strength and strength–post-uniform elongation in DP steels. Quantitative analysis of void formation reveals that fracture by martensite cracking is a primary fracture mechanism in coarse phase-sized DP samples, while ferrite/martensite interface decohesion becomes a dominant fracture mechanism in fine phase-sized DP samples. It is suggested that the refinement of phase size is a promising strategy to change the fracture behavior from brittle to ductile manner, leading to an enhancement of local deformability after the necking.
AB - This study investigates the effect of ferrite/martensite phase size and dispersion of nano-precipitates in ferrite on strength, ductility, and fracture behavior of dual-phase (DP) steels. Dispersion of nano-precipitates in ferrite improves the strength with keeping sufficient uniform elongation and post-uniform elongation, while decrease in ferrite/martensite phase size has a little effect on the increase in strength in the phase size range investigated. However, the refinement of phase size significantly improves the post-uniform elongation and reduction in area. It is concluded therefore that a simultaneous combination of refinement of ferrite/martensite phase size and dispersion of nano-precipitation in ferrite is effective to significantly improve the strength and strength–post-uniform elongation in DP steels. Quantitative analysis of void formation reveals that fracture by martensite cracking is a primary fracture mechanism in coarse phase-sized DP samples, while ferrite/martensite interface decohesion becomes a dominant fracture mechanism in fine phase-sized DP samples. It is suggested that the refinement of phase size is a promising strategy to change the fracture behavior from brittle to ductile manner, leading to an enhancement of local deformability after the necking.
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U2 - 10.1007/s11661-019-05353-3
DO - 10.1007/s11661-019-05353-3
M3 - Article
AN - SCOPUS:85068859517
VL - 50
SP - 4111
EP - 4126
JO - Metallurgical Transactions A (Physical Metallurgy and Materials Science)
JF - Metallurgical Transactions A (Physical Metallurgy and Materials Science)
SN - 1073-5623
IS - 9
ER -