[P91] Thermodynamic and Kinetic Modeling of the Ferrite-Austenite Phase Transformation

The phase transformation characteristics, the dynamic elastic modulus and the static tensile elastic modulus of Ti50Ni47.5Fe2.5 alloy were investigated. It is found that, the two mutations in the dynamic elastic modulus is caused by reverse martensite phase transformation and austenite phase transformation respectively; Static tensile test can not reflect the intrinsic elastic modulus when the test temperature is close to martensite transformation temperature(Ms). The static elastic modulus and the dynamic elastic modulus have the same trend when the test temperature is enough higher than Ms.

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In Situ Neutron Diffraction Study of Phase Transformation of High Mn Steel with Different Carbon Content

Crystals ◽

10.3390/cryst10020101 ◽

2020 ◽

Vol 10 (2) ◽

pp. 101

Author(s):

Youngsu Kim ◽

Wookjin Choi ◽

Hahn Choo ◽

Ke An ◽

Ho-Suk Choi ◽

...

Keyword(s):

Phase Transformation ◽

Neutron Diffraction ◽

Strain Hardening ◽

High Strain ◽

Tensile Deformation ◽

Austenite Phase ◽

Transformation Rate ◽

Ε Martensite ◽

In Situ Neutron Diffraction

In situ neutron diffraction was employed to examine the phase transformation behavior of high-Mn steels with different carbon contents (0.1, 0.3, and 0.5 wt.%C). With increasing carbon contents from 0.1 C to 0.5 C, the austenite phase fraction among the constituent phases increased from ~66% to ~98%, and stacking fault energy (SFE) increased from ~0.65 to ~16.5 mJ/m2. The 0.1 C and 0.3 C steels underwent phase transformation from γ-austenite to ε-martensite or α’-martensite during tensile deformation. On the other hand, the 0.5 C steel underwent phase transformation only from γ-austenite to ε-martensite. The 0.3 C steel exhibited a low yield strength, a high strain hardening rate, and the smallest elongation. The high strain hardening of the 0.3 C alloy was due to a rapid phase transformation rate from γ-austenite to ε-martensite. The austenite of 0.5 C steel was strengthened by mechanical twinning during loading process, and the twinning-induced plasticity (TWIP) effect resulted in a large ductility. The 0.5 wt.% carbon addition stabilized the austenite phase by delaying the onset of the ε-martensite phase transformation.

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Effect of initial microstructures prior to cold-rolling and intercritical annealing on ferrite recrystallization and ferrite-to-austenite phase transformation in Nb bearing low-carbon steels

Journal of Physics Conference Series ◽

10.1088/1742-6596/1270/1/012016 ◽

2019 ◽

Vol 1270 ◽

pp. 012016

Author(s):

Toshio Ogawa ◽

Hiroyuki Dannoshita ◽

Yoshitaka Adachi ◽

Kohsaku Ushioda

Keyword(s):

Phase Transformation ◽

Cold Rolling ◽

Intercritical Annealing ◽

Carbon Steels ◽

Austenite Phase ◽

Low Carbon ◽

Low Carbon Steels

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Orientation Relationship during Partial α-γ-Phase Transformation in Microalloyed Steels

Materials Science Forum ◽

10.4028/www.scientific.net/msf.495-497.447 ◽

2005 ◽

Vol 495-497 ◽

pp. 447-452 ◽

Cited By ~ 9

Author(s):

I. Lischewski ◽

Günter Gottstein

Keyword(s):

Phase Transformation ◽

Orientation Relationship ◽

Microalloyed Steel ◽

Austenite Phase ◽

Microalloyed Steels ◽

Special Focus ◽

Partial Phase ◽

Growth Selection

The ferrite to austenite phase transformation in microalloyed steel was studied, with a special focus on the orientation relationship between prior ferrite and subsequent austenite. Also the role of growth selection and preferred nucleation was investigated in this context. Their effects were examined at partial phase transformation.

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