Comparison of solidification behavior between in situ observation and simulation of Fe–C–Si system

Abstract

Please cite this article as: H.M. Henao, A. Sugiyama, K. Nogita, Comparison of solidification behavior between insitu observation and simulation of Fe-C-Si system, (2014), doi: http://dx.doi.org/10. 1016/j.jallcom.2014.05.184 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Key words: metals and alloys; crystal growth; kinetics; computer simulations; synchrotron radiation Comparison of solidification behavior between in-situ observation and simulation of Fe-C-Si system AbstractOver the last few years, important advances have been made in the understanding and modelling of phase transformations of metallic alloys including a) the coupling of phase equilibria and kinetics for computerised simulation of multicomponent alloys and b) in-situ time resolved X-ray imaging of phase transformations in real time. Both techniques can be complementary. However the quality of the simulation relies to a large extent on the accuracy of phase equilibria and diffusion data obtained from existing experimental studies. In-situ Xray techniques provide quantitative information on the evolution and proportion of phases, and can validate the thermodynamic/kinetic packages. This validation in-turn improves the computational models and databases. In the present work, the phase transformation in the Fe-C-Si system from liquid to γ-Fe and the reaction liquid↔γ-Fe+Cementite was observed by using X-ray imaging at SPring-8 synchrotron. The relationship between fraction solid and temperature was obtained from the generated SPring-8 images. The results are compared with computer simulation using Thermo-Calc. and DICTRA. A critical analysis compares the results of the simulation with the real-time observations of the phase transformation.

Microsegregation and solidification characteristics of an advanced high strength steel – part II: experimental validation

“…Although the microstructures are obtained from different samples, they can be considered as different stages of an entire solidification process. During solidification, dendrites are grown by gradually consuming residual liquids, and there is a mathematical relationship between the temperature and the fraction of solids (or liquids), which can be influenced by the composition and solidification condition of steels [34]. In this work, the evolution of the solid fraction was statistically determined by the area ratio of the solid phase.…”

“…Many attempts have been made to determine the evolution of the solid fraction in thermally controlled conditions, including scanning thermal analysis of calorimetry and image analysis of solidification structures. An in situ X-ray technique has been adopted to study the solidification behaviours of Fe-C and Fe-C-Si systems [34]. The relationship between the fraction solid and temperature was obtained from the images of in situ observations, which were compared with computer simulation using Thermo-Calc and DICTRA to validate the thermodynamic/kinetic database [34].…”

“…An in situ X-ray technique has been adopted to study the solidification behaviours of Fe-C and Fe-C-Si systems [34]. The relationship between the fraction solid and temperature was obtained from the images of in situ observations, which were compared with computer simulation using Thermo-Calc and DICTRA to validate the thermodynamic/kinetic database [34]. It has been reported that some solid can coat on the prior dendrites during quenching due to the low cooling rate of quenching when performing directional solidification [1].…”

Experimental investigation and thermodynamic calculation of the Fe–Si–Sn system

“…There are three constituting binaries in the Fe-Si-Sn ternary system, Fe-Si, Fe-Sn and Si-Sn systems. The Fe-Si binary system thermodynamically assessed by Lacaze and Sundman [9] has been widely accepted in literature [10][11][12][13]. As presented in Fig.…”