Kinetic transitions during non-partitioned ferrite growth in Fe–C–X alloys

✍ Scribed by H.S. Zurob; C.R. Hutchinson; Y. Bréchet; H. Seyedrezai; G.R. Purdy

• Book ID: 103998805
• Publisher: Elsevier Science
• Year: 2009
• Tongue: English
• Weight: 782 KB
• Volume: 57
• Category: Article
• ISSN: 1359-6454
• DOI: 10.1016/j.actamat.2009.02.029

✦ Synopsis

Ferrite growth behavior in Fe-C-Mn alloys has been studied using controlled decarburization experiments. The recently reported transition from LENP (local equilibrium-negligible partitioning) kinetics, at lower temperatures, to PE (paraequilibrium) kinetics, at higher temperatures, is shown to behave self-consistently over a range of Mn contents and temperatures and long-lived intermediate states between LENP and PE persist over a well-defined range of temperature and composition. A simple model which quantitatively describes the experimental observations over a range of composition and temperature is proposed. A key feature of this model is the introduction of an alloying element capacity of the moving a/c interface, X Ã Mn . The introduction of this quantity is purely guided by the experimental data and, at present, there is no physically based method for calculating it. Once X Ã Mn is defined, multiple-jump kinetic analysis quantitatively describes the experimental observations over an impressive range of growth behaviors.