TY - JOUR
T1 - Strain-induced transformation behaviour of retained austenite and tensile properties of TRIP-aided steels with different matrix microstructure
AU - Mukherjee, Monideepa
AU - Mohanty, Omkar Nath
AU - Hashimoto, Shun Ichi
AU - Hojo, Tomohiko
AU - Sugimoto, Koh Ichi
PY - 2006
Y1 - 2006
N2 - The effects of strain rate and temperature on the strain induced transformation behaviour of retained austenite and hence mechanical properties of TRIP-aided steels with annealed martensite (AM), bainitic ferrite (BF) and polygonal ferrite (PF) matrix microstructures were examined. For this, tensile tests were carried out at four different strain rates varying from 3.33×10-5 s-1 to 3.33×10-2 s -1 at room temperature and at 150°C. Additional intermittent tests were carried out at intermediate strain rates to estimate the extent of strain induced transformation of austenite to martensite using X-ray diffraction analysis. Tensile strength (TS) decreased with strain rate at both temperatures, though the TS at 150°C was lower for all steels except for BF steel tested at 3.33×10-5s-1. The total elongation (TEL) for PF steel significantly improved at 150°C at all strain rates, with a maximum of 78% obtained at 3.33×10-3 s-1, the corresponding TS being 930MPa. A similar effect was seen in AM steels tested at 3.33×10-3s-1 and 3.33×10-4s -1. However, in BF steel, higher temperature had a detrimental effect on TEL, especially at strain rates of 3.33×10-2 s-1 and 3.33×10-3s-1.
AB - The effects of strain rate and temperature on the strain induced transformation behaviour of retained austenite and hence mechanical properties of TRIP-aided steels with annealed martensite (AM), bainitic ferrite (BF) and polygonal ferrite (PF) matrix microstructures were examined. For this, tensile tests were carried out at four different strain rates varying from 3.33×10-5 s-1 to 3.33×10-2 s -1 at room temperature and at 150°C. Additional intermittent tests were carried out at intermediate strain rates to estimate the extent of strain induced transformation of austenite to martensite using X-ray diffraction analysis. Tensile strength (TS) decreased with strain rate at both temperatures, though the TS at 150°C was lower for all steels except for BF steel tested at 3.33×10-5s-1. The total elongation (TEL) for PF steel significantly improved at 150°C at all strain rates, with a maximum of 78% obtained at 3.33×10-3 s-1, the corresponding TS being 930MPa. A similar effect was seen in AM steels tested at 3.33×10-3s-1 and 3.33×10-4s -1. However, in BF steel, higher temperature had a detrimental effect on TEL, especially at strain rates of 3.33×10-2 s-1 and 3.33×10-3s-1.
KW - Annealed martensite
KW - Bainitic ferrite
KW - Ductility
KW - Microstructure
KW - Morphology
KW - Retained austenite
KW - TRIP
KW - Tensile property
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U2 - 10.2355/isijinternational.46.316
DO - 10.2355/isijinternational.46.316
M3 - Article
AN - SCOPUS:33646043803
VL - 46
SP - 316
EP - 324
JO - Transactions of the Iron and Steel Institute of Japan
JF - Transactions of the Iron and Steel Institute of Japan
SN - 0915-1559
IS - 2
ER -