Influence of Nb Microaddition on Microstructure and Texture Evolution in a Fe-21Mn-1.3Al-1.5Si-0.5C TWIP Steel under Uni
- PDF / 626,964 Bytes
- 7 Pages / 432 x 648 pts Page_size
- 91 Downloads / 201 Views
MRS Advances © 2017 Materials Research Society DOI: 10.1557/adv.2017.600
Influence of Nb Microaddition on Microstructure and Texture Evolution in a Fe-21Mn-1.3Al-1.5Si0.5C TWIP Steel under Uniaxial Hot-Tensile Conditions A.E. Salas-Reyes1,2, I. Mejía1 and J.M. Cabrera3. 1
Instituto de Investigación en Metalurgia y Materiales, Universidad Michoacana de San Nicolás de Hidalgo, 58066-Morelia, Michoacán, México. E-mail: [email protected], [email protected]
2
Departamento de Ingeniería Metalúrgica, Facultad de Química, Universidad Nacional Autónoma de México, Circuito Exterior s/n, Coyoacán, Cd. Universitaria, 04510-Ciudad de México, México.
3 Departament de Ciència dels Materials i Enginyeria Metal·lúrgica, EEBE-Universitat Politècnica de Catalunya, c/Eduard Maristany 10-14, Edif. I, Of 1.18, 08019-Barcelona, Spain.
ABSTRACT
Advanced high-strength steels as Twinning Induced Plasticity (TWIP) steels have been developed using microalloying elements and subsequent thermo-mechanical processing techniques. Moreover, under hot-working conditions, these steels undergo significant microstructural changes as a result of preferred crystallographic orientation (texture) of grains. In order to evaluate this behavior, one non-microalloyed and other single Nbmicroalloyed TWIP steels were melted in an induction furnace and cast into metal and sand molds. Samples with austenitic grain sizes between 400 and 2000 μm were deformed at 800 °C and strained at a constant strain rate of 10-3 s-1, and deformation state was examined by means of electron backscatter diffraction (EBSD) technique near to the fracture tip. It was found that non-microalloyed TWIP steel solidified in both metal and sand mold exhibits dynamically recrystallized grains. On the other hand, Nb microaddition has a strong influence in TWIP steel retarding the onset of recrystallization kinetics, showing low angle sub-structured grains. Furthermore, it was possible identifying the crystallographic orientation of grains using the inverse pole figures (IPF) and the orientation distribution function (ODF). Weak cube {001} recrystallization and E{111} γ-fiber deformation textures components were detected.
INTRODUCTION High-Mn austenitic steels with up to 30 wt.% Mn and more than 0.4 wt.% C have one of the best combination of the strength and plasticity among the currently 3797
Downloaded from https://www.cambridge.org/core. Access paid by the UCSB Libraries, on 11 Mar 2018 at 11:46:33, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1557/adv.2017.600
available steels. This is due to the twinning-induced plasticity (TWIP) effect that occurs at room temperature but progressively transforms to dislocation glide when deformation temperature increases [1]. However, it has been shown that TWIP alloys have naturally low yield strength (YS) [2]. Accordingly, there is a clear benefit in increasing the yield strength through Nb, Ti, or V microalloying elements, operation that can be an ideal hardening mecha
Data Loading...