Experimental model of the pearlite interlamellar spacing in lamellar graphite iron
Vasilios Fourlakidis, Ilia Belov, Attila Diószeg
Abstract
The pearlite lamellar spacing (λpearlite) is one of the microstructure parameters that define the strength of the lamellar graphite iron (LGI). The transformation kinetics of λpearlite has been the subject of several modeling studies for steels, which demonstrated that the λpearlite can be calculated as a function of undercooling. However, it is hard to find in the literature the models for the prediction of λpearlite in LGI. In the present work, λpearlite in fully pearlitic LGI was investigated for a wide range of carbon contents and cooling rates. The undercooling and the cooling rates were estimated from the experimental cooling curves and were utilized for the prediction of λpearlite. The experimental data analysis provides an empirical expression that correlates λpearlite and cooling rates from the eutectoid transformation region. The developed empirical model was incorporated into a casting simulation software to enable the prediction of λpearlite in LGI and the simulation results were found to be in good agreement with the experimental data.
Keywords
References
1 Marder AR, Bramfitt BL. The effect of morphology on the strength of pearlite. MTA. 1976;7(3):365-372.
2 Elwazri AM, Wanjara P, Yue S. The effect of microstructural characteristics of pearlite on the mechanical properties of hypereutectoid steel. Materials Science and Engineering A. 2005;404(1-2):91-98.
3 Catalina A, Guo X, Stefanescu DM, Chuzhoy L, Pershing MA. Prediction of room temperature microstructure and mechanical properties in lamellar iron castings. AFS Trans. 2000;94:889-912.
4 Sjögren T, Svensson H. Study of the eutectoid transformation in grey cast irons and its effect on mechanical properties. Key Engineering Materials. 2010;457:157-162.
5 Fourlakidis V, Diószegi A. A generic model to predict the ultimate tensile strength in pearlitic lamellar graphite iron. Materials Science and Engineering A. 2014;618:161-167.
6 Fourlakidis V, Diaconu L, Diószegi A. Strength prediction of Lamellar Graphite Iron: from Griffith’s to Hall-Petch modified equation. Trans Tech Publications. 2018;925:272-279.
7 Mehl RF, Hagel WC. The austenite: pearlite reaction. Progress in Metal Physics. 1956;6:74-134.
8 Marder AR, Bramfitt BL. Effect of continuous cooling on the morphology and kinetics of pearlite. MTA. 1975;6(11):2009-2014.
9 Caballero FG, Capdevila C, Garcia de Andres C. Modeling of the interlamellar spacing of isothermally formed pearlite in a eutectoid steel. Cripta Materialia. 2000;42(6):537-542.
10 Pernach M. Application of the mixed-mode model for numerical simulation of pearlitic transformation. Journal of Materials Engineering and Performance. 2019;28(5):3136-3148.
11 Takahashi M. Reaustenitization from bainite in steels [thesis]. Cambridge: University of Cambridge; 1992.
12 Lacaze J. Pearlite growth in cast irons: a review of literature data. International Journal of Cast Metals Research. 1999;11(5):431-436.
13 Stefanescu DM. Modeling of cast iron solidification: the defining moments. Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science. 2007;38:1433-1447.
14 Svensson H, Sjögren T. The effect of cooling rate, section size and alloying on matrix structure formation in pearlitic grey cast iron. Key Engineering Materials. 2010;457:169-174.
15 Freulon A, Sertucha J, Lacaze J. Solidification and room temperature microstructure of a fully pearlitic compacted graphite cast iron. Transactions of the Indian Institute of Metals. 2018;71(11):2651-2656.
16 Aranda MM, Kim B, Rementeria R, Capdevila C, de Andrés CG. Effect of Prior Austenite Grain Size on Pearlite Transformation in a Hypoeuctectoid Fe-C-Mn Steel. Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science. 2014;45(4):1778-1786.
17 Pellissier GE. The interlamellar spacing of pearlite. Trans. ASM. 1942;30:1049-1086.
18 Barkhudarov MR, Hirt CW. Casting simulation: mold filling and solidification: benchmark calculations using FLOW-3D. Santa Fe, NM: Flow Science, Inc.; 1993. (Technical report) [cited 2021 Sept. 2]. Available at: https://www.flow3d.com/wp-content/uploads/2014/08/Casting-Simulation-Mold-Filling-and-Solidification-BenchmarkCalculations-Using-FLOW-3D.pdf
19 Fourlakidis V, Belov I, Diószegi A. Strength prediction for pearlitic lamellar graphite iron: model validation. Metals. 2018;8(9):684.
20 Alonso G, Larrañaga P, Sertucha J, Suárez R, Stefanescu DM. Gray cast iron with high austenite-to-eutectic ratio part I- calculation and experimental evaluation of the fraction of primary austenite in cast iron. Trans. AFS. 2012;120:329-335.
21 Sertucha J, Larrañaga P, Lacaze J, Insausti M. Experimental investigation on the effect of copper upon eutectoid transformation of as-cast and austenitized spheroidal graphite cast iron. Inter Metalcast. 2010;4(1):51-58.
22 Kramer JJ, Pound GM, Mehl RF. The free energy of formation and the interfacial enthalpy in pearlite. Acta Metallurgica. 1958;6(12):763-771.
23 Ridley N. A review of the data on the interlamellar spacing of pearlite. MTA. 1984;15(6):1019-1036.
Submitted date:
09/02/2021
Accepted date:
12/08/2021