Texture inheritance and variant selection through an hcp–bcc–hcp phase transformation

The orientation relationships that apply to the fcc (γ) – bcc (α) phase transformation in high-performance hot-rolled TRIP-aided steels were characterised by EBSD techniques. A statistical treatment of the experimental data allows the mean orientation relationship to be determined. This mean orientation relationship was compared to the models commonly proposed in the literature and confronted qualitatively to the predictions of the phenomenological theory of martensite crystallography (PTMC). The variant selection phenomenon was also characterized quantitatively at the level of individual austenite grains. The reconstruction of the EBSD maps evidences that bainite grows by packets in which the bainite laths share a common {111}γ plane in the austenite. This growth mechanism is not influenced by the prior hot deformation of the austenite. The hot deformation has a critical influence on the number of packets that forms. The analysis of the crystallographic features of the bainite packets reveals that all possible variants are formed in a packet, though in different proportions.

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Orientation Relationships and Variant Selection during α- to γ- Phase Transformation in Low Carbon Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.408-412.1191 ◽

2002 ◽

Vol 408-412 ◽

pp. 1191-1196 ◽

Cited By ~ 1

Author(s):

C.M. Park ◽

G. Brückner ◽

Günter Gottstein

Keyword(s):

Phase Transformation ◽

Carbon Steel ◽

Low Carbon Steel ◽

Variant Selection ◽

Low Carbon ◽

Orientation Relationships

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Evolution of Grain Boundary Texture in Zirconium Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.702-703.710 ◽

2011 ◽

Vol 702-703 ◽

pp. 710-713

Author(s):

Karri V. Mani Krishna ◽

Sudipto Mandal ◽

Ankur Agrawal ◽

Vijay Hiwarkar ◽

Dinesh Srivastava ◽

...

Keyword(s):

Phase Transformation ◽

Grain Boundary ◽

Annealing Time ◽

Considerable Increase ◽

Direct Evidence ◽

Texture Evolution ◽

Zirconium Alloys ◽

Alpha Phase ◽

Variant Selection ◽

Alpha Beta

Grain boundary texture evolution in case of two of the Zr based alloys (Zircaloy-4 and Zr-2.5\%Nb) was studied. In case of Zircaloy-4, grain boundary texture evolution during $\beta$ $\to$ $\alpha$ phase transformation was monitored. Direct evidence of variant selection during this transformation is presented. In case of Zr-2.5\%Nb alloy, considerable increase in $\alpha/\beta$ interfaces following Burger's orientation relationship was noticed with increasing annealing time at 700 \textdegree{}C.

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The influence of rolling temperature on texture evolution and variant selection during α→β→α phase transformation in Ti–6Al–4V

Acta Materialia ◽

10.1016/j.actamat.2012.07.025 ◽

2012 ◽

Vol 60 (17) ◽

pp. 6013-6024 ◽

Cited By ~ 45

Author(s):

G.C. Obasi ◽

S. Birosca ◽

D.G. Leo Prakash ◽

J. Quinta da Fonseca ◽

M. Preuss

Keyword(s):

Phase Transformation ◽

Texture Evolution ◽

Rolling Temperature ◽

Variant Selection ◽

Α Phase

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Variant selection in surface martensite

Journal of Applied Crystallography ◽

10.1107/s160057671701398x ◽

2017 ◽

Vol 50 (6) ◽

pp. 1646-1652 ◽

Cited By ~ 5

Author(s):

Annick P. Baur ◽

Cyril Cayron ◽

Roland E. Logé

Keyword(s):

Phase Transformation ◽

Habit Plane ◽

Phenomenological Theory ◽

Martensitic Phase ◽

Martensitic Phase Transformation ◽

Variant Selection ◽

Related Variant ◽

Accommodation Mechanism

A significant variant selection is reported in isothermal martensite formed on the surface of an Fe–30% Ni sample. The selection phenomenon is modelled using different descriptions of the martensitic phase transformation. In particular, matrices based on the phenomenological theory of martensite crystallography, the Jaswon and Wheeler distortion, and the continuous face centred cubic–body centred cubic distortion are compared. All descriptions allow good predictions of the variant selection. However, the Jaswon and Wheeler distortion and the continuous distortion better account for other features of the surface martensite, such as the {225}γhabit plane and the accommodation mechanism by twin-related variant pairing.

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