Analysis of Bainite Onset During Cooling Following Prior Deformation at Different Temperatures

Analysis of Bainite Onset During Cooling Following Prior Deformation at Different Temperatures

Aarne Pohjonen, Antti Kaijalainen, Mahesh Somani, Jari Larkiola

University of Oulu, Pentti Kaiteran katu 1, 90014 Oulu, Finland.



We apply method for calculating the austenite to bainite phase transformation onset for any cooling path for a steel of composition 0.09C, 0.2Si, 1.0Mn, 0.03Al, 1.1Cr, 0.18Mo, 0.026Ti, 0.0018B (wt. %) following deformation at different temperatures. The method is parameterized by constant cooling rate experiments to obtain the CCT diagram of this steel following deformation either above recrystallization limit temperature (RLT) or below the no-recrystallization temperature (Tnr). Using the CCT diagrams, we have performed analytical/numerical analysis of the transformation onset, which is based on the conversion of CCT to ideal TTT transformation diagram by the inversion of Scheil’s additivity rule. After the conversion, the transformation onset can be calculated for any cooling path by applying Scheil’s additivity rule. The analysis also provides information on the thermal activation parameters of the transformation onset. The discussion of the results is also provided.

Cite as:

Pohjonen, A., Kaijalainen, A., Somani, M., Larkiola, J. (2017). Analysis of Bainite Onset During Cooling Following Prior Deformation at Different Temperatures. Computer Methods in Materials Science, 17(1), 30 – 35.

Article (PDF):


Bainite, Deformation, Phase Transformation, Nucleation, CCT diagram, TTT diagram


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