The phase-field approach and solute drag modeling of the transition to massive γ → α transformation in binary Fe-C alloys

✍ Scribed by I. Loginova; J. Odqvist; G. Amberg; J. Ågren

• Publisher: Elsevier Science
• Year: 2003
• Tongue: English
• Weight: 169 KB
• Volume: 51
• Category: Article
• ISSN: 1359-6454
• DOI: 10.1016/s1359-6454(02)00527-x

✦ Synopsis

The transition between diffusion controlled and massive transformation g →α in Fe-C alloys is investigated by means of phase-field simulations and thermodynamic functions assessed by the Calphad technique as well as diffusional mobilities available in the literature. A gradual variation in properties over an incoherent interface, having a thickness around 1 nm, is assumed. The phase-field simulations are compared with a newly developed technique to model solute drag during phase transformations. Both approaches show qualitatively the same behavior and predict a transition to a massive transformation at a critical temperature below the T 0 line and close to the a/a + g phase boundary. It is concluded that the quantitative difference between the two predictions stems from different assumptions on how the properties vary across the phase interface yielding a lower dissipation of Gibbs energy by diffusion in the phase-field simulations. The need for more detailed information about the actual variation in interfacial properties is emphasized.