A phase-field model for bainitic transformation

• Published in: Computational materials science 2013-09, Vol.77, p.230-235
• Main Authors: Arif, T.T., Qin, R.S.
• Format: Article
• Language: English
• Subjects: Autocatalysis; Bainite transformation; Calibration; Computation; Constant-composition solid-solid phase transformations: polymorphic, massive, and order-disorder; Cross-disciplinary physics: materials science; rheology; Crystal structure; Cubic crystal; Displacement; Displacive phase transitions; Evolution; Exact sciences and technology; Free energy; Materials science; Mathematical models; Phase diagrams and microstructures developed by solidification and solid-solid phase transformations; Phase-field model; Physics; Transformations
• ISSN: 0927-0256; 1879-0801
• DOI: 10.1016/j.commatsci.2013.04.044

•The autocatalysis commonly seen in bainitic transformations is reproduced after adequate calibration.•The chemical free energy is incorporated into the driving force.•The anisotropic elastic contribution is incorporated into the driving force.•After adequate calibration, the results show carbon entrapment between subunits agreeing with experiments.•The model is capable of reproducing the incomplete transformation phenomenon after adequate calibration. A phase-field model for the computation of microstructure evolution for the bainite transformation has been developed. The model has a classical phase-field foundation, incorporates the phenomenological displacive transformation theory and the symmetric analysis of cubic crystals, and is able to reproduce realistic grain morphology and crystal orientation after adequate calibration. Using the free energy expression for the shape change of displacive transformations along with the free energy formula for the chemical free energy change of the two phases derived from established regular solution models, the current model is able to deal with autocatalysis.