Ordering of carbon in highly supersaturated α-Fe. (12th December 2018)

• Record Type: Journal Article
• Authors: Waseda, Osamu; Morthomas, Julien; Ribeiro, Fabienne; Chantrenne, Patrice; Sinclair, Chad W; Perez, Michel
• Is Part Of: Modelling and simulation in materials science and engineering. Volume 27:Number 1(2019)
• Publication Date: 2018-12-12
• Subjects: ordering -- Monte Carlo -- molecular dynamics -- Fe–C; Materials -- Mathematical models -- Periodicals; Matériaux -- Modèles mathématiques -- Périodiques; Materials -- Mathematical models; Periodicals; 620.00113
• DOI: 10.1088/1361-651X/aaef22
• Languages: English
• ISSNs: 0965-0393

Abstract

Abstract: Metropolis Monte Carlo is used to investigate the Zener ordering as the carbon content of body centered cubic iron is increased. Thanks to a fast simulation algorithm, the equilibrium state for a wide range of temperature and carbon content are investigated. These results are compared to a thermodynamical mean-field model that accounts for long range elastic interaction and configurational entropy. At carbon levels of above 2 at.%, it is found that the mean-field model overestimates the order–disorder transition temperature. This is due to local repulsive C–C interactions not accounted for in the mean-field model. Forbidding some strongly repulsive configurations leads to a better agreement between the mean-field model and Metropolis Monte Carlo simulations. At high concentration carbon atoms in solid solution exhibits local configurations typical of the Fe16 C2 carbide.