Numerical Model for Solidification Zones Selection in the Large Ingots

Open access

Abstract

A vertical cut at the mid-depth of the 15-ton forging steel ingot has been performed by curtesy of the CELSA - Huta Ostrowiec plant. Some metallographic studies were able to reveal not only the chilled undersized grains under the ingot surface but columnar grains and large equiaxed grains as well. Additionally, the structural zone within which the competition between columnar and equiaxed structure formation was confirmed by metallography study, was also revealed. Therefore, it seemed justified to reproduce some of the observed structural zones by means of numerical calculation of the temperature field. The formation of the chilled grains zone is the result of unconstrained rapid solidification and was not subject of simulation. Contrary to the equiaxed structure formation, the columnar structure or columnar branched structure formation occurs under steep thermal gradient. Thus, the performed simulation is able to separate both discussed structural zones and indicate their localization along the ingot radius as well as their appearance in term of solidification time.

[1] Hunt, J.D. (1984). Steady State Columnar and Equiaxed Growth of Dendrites and Eutectics. Materials Science and Engineering 65, 75-83.

[2] Gu, J.P. & Beckermann, C. (1999). Simulation of Convection and Macrosegregation in a Large Steel Ingot. Metallurgical and Materials Transactions 30A, 1357-1366.

[3] Gandin, Ch.A. (2000). From Constrained to Unconstrained Growth during Directional Solidification. Acta Materialia 48, 2483-2501.

[4] Gandin, Ch.A. (2000). Experimental Study of the Transition from Constrained to Unconstrained Growth during Directional Solidification. The Iron and Steel Institute of Japan-International 40, 971-979.

[5] Wołczyński, W. (2010). Constrained / Unconstrained Solidification within the Massive Cast Steel / Iron Ingots. Archives of Foundry Engineering 10 (2), 195-202.

[6] Bogdan, O. (2010). Numerical Analysis of Casting Technology and A-Segregation Prediction in AISI 4340 Forgings Products. Industrial Soft 1, 1-12.

[7] Wołczyński, W., Kania, B., Wajda, W. & Kostrzewa, M. (2011). Space - Time - Structure Map for as Cast Massive Rolls. In Fundamentals of Heat and Mass Transfer - Computational Heat and Mass Transfer, Proceedings of the ASME/JSME 8-th Thermal Engineering Joint Conference - AJTEC, March 13-17, 2011. Conference CD: AJTEC-44021, 3.1. Honolulu, Hawaii, USA,; Hishida, K., Klausner, J., Satoh, I., Eds.; ASME/JSME.

[8] Szajnar, J. (2004).The Columnar Crystals Shape and Castings Structure Cast in Magnetic Field. Journal of Materials Processing Technology 157/158, 761-764.

[9] Gandin, Ch.A., Mosbah, S., Volkmann, Th. & Herlach, D.M. (2008). Experimental and Numerical Modeling of Equiaxed Solidification in Metallic Alloys. Acta Materialia 56, 3023-3035.

[10] McFadden, S., Browne, D.J. & Gandin, Ch.A. (2009). A Comparison of CET Prediction Methods using Simulation of the Growing Columnar Front. Metallurgical Transactions 40A, 662-672.

[11] Konozsy, L., Ishmurzin, A., Grasser, M., Wu, M.H., Ludwig, A., Tanzer, R. & Schutzenhofer, W. (2010). Columnar to Equiaxed Transition during Ingot Casting using Ternary Alloy Composition. Materials Science Forum 649, 349-354.

[12] Vusanović, I. & Voller, V.R. (2014). Understanding Channel Segregates in Numerical Models of Alloy Solidification: A Case of Converge First and Ask Questions Later. Materials Science Forum 790/791, 73-78.

[13] Zimmermann, G., Sturz, L., Billia, B., Mangelinck-Noel, N.; Liu, D.R. Nguyen Thi, H., Bergeon, N., Gandin, Ch.A., Browne, D.J., Beckermann, C., Tourret, D. & Karma, A. (2014). Columnar-to-Equiaxed Transition in Solidification Processing of AlSi7 Alloy in Microgravity -The CETSOL Project. Materials Science Forum 790/791, 12-21.

[14] Wołczyński, W., Guzik, E., Wajda, W., Jędrzejczyk, D., Kania, B. & Kostrzewa, M. (2012). CET in Solidifying Roll - Thermal Gradient Field Analysis. Archives of Metallurgy and Materials 57 (1), 105-117.

[15] Wołczyński, W., Wajda, W. & Guzik, E. (2013). Thermal Gradients Behaviour during the C-E Transition within Solidifying Massive Roll. Solid State Phenomena 197, 174-179.

[16] Wołczyński, W., Guzik, E., Kania, B. & Wajda, W. (2010). Structure Fields in the Solidifying Cast Iron Roll. Archives of Foundry Engineering 10 (1), 41-46.

[17] Wołczyński, W. (2015). Mathematical Modeling of the Microstructure of Large Steel Ingots, Entry in: The Encyclopedia of Iron, Steel, and Their Alloys, Eds. Taylor & Francis Group, (in print), New York-USA.

[18] ABAQUS Theory Manual, Academic Computer Centre - CYFRONET, AGH University of Science & Technology, Kraków.

[19] Trepczyńska-Łent, M. (2013). Possibilities of the Materials Properties Improvement for the Cementite Eutectic by means of Unidirectional Solidification, Archives of Metallurgy and Materials 58, 987-991.

Archives of Foundry Engineering

The Journal of Polish Academy of Sciences

Journal Information


CiteScore 2016: 0.42

SCImago Journal Rank (SJR) 2016: 0.192
Source Normalized Impact per Paper (SNIP) 2016: 0.316

Metrics

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 204 164 13
PDF Downloads 88 75 3