2024-03-29T12:48:32Z
https://soar-ir.repo.nii.ac.jp/oai
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2022-12-14T04:12:28Z
1221:1222
Effects of Microalloying on Stretch-flangeability of Ultrahigh-strength TRIP-aided Martensitic Steel Sheets
Duc, Van Pham
Kobayashi, Junya
Sugimoto, Koh-ichi
stretch-flangeability
microalloying
ultrahigh-strength steel
TRIP-aided steel
retained austenite
martensite
The effects of Cr, Mo, and Ni addition on the microstructure and stretch-flangeability of a 0.2%C-1.5%Si-1.5%Mn-0.05%Nb (mass%) transformation-induced plasticity (TRIP)-aided martensitic steel sheet produced by an isothermal transformation process at a temperature below martensite transformation-finish temperatures were investigated in order to develop third-generation steel sheet for automobiles requiring high hardenability. When 0.5% or 1.0% Cr was added to the base steel, a tensile strength of 1.5 GPa and a hole-expanding ratio of 40% was attained. On the other hand, the addition of Cr-Mo or Cr-Mo-Ni had a minimal influence on stretch-flangeability and stretch-formability, although it increased the yield and tensile strengths as compared to the base steel. The good balance of the Cr-bearing steel was mainly caused by a suitable combination of (1) volume fraction and (2) interparticle path of a finely dispersed martensite-austenite complex phase, which suppressed void initiation at the matrix/complex-phase interface on hole-punching and void coalescence or crack extension on hole-expanding.
Article
ISIJ INTERNATIONAL. 54(8):1943-1951 (2014)
journal article
IRON STEEL INST JAPAN KEIDANREN KAIKAN
2014-10-30
application/pdf
ISIJ INTERNATIONAL
8
54
1943
1951
0915-1559
AA10680712
https://soar-ir.repo.nii.ac.jp/record/18002/files/Effects_Microalloying_Stretch-flangeability_Ultrahigh-strength.pdf
eng
10.2355/isijinternational.54.1943
https://doi.org/10.2355/isijinternational.54.1943
Copyright © 2014 ISIJ