Competitive Nucleation in Grey Cast Irons

• Autorzy: Arab N.

Identyfikatory

DOI

10.1515/afe-2017-0155

• Języki publikacji: EN

Abstrakty

EN

Cast irons are good examples of materials which are more sensitive to chemical composition and production conditions. In this research to improve casting quality, solidification and nucleation process in grey cast iron was investigate. In particular, attempts have been made to rationalize variation in eutectic cells with nucleation sites and eutectic solidification undercooling. Four castings with different diameter and similar chemical composition and pouring temperature and different inoculant percentage was casted. The cooling curve and maximum and minimum undercooling for each castings was measured. Also optical metallography and image analyzer has been used to determine the average eutectic cells diameter, and linear and surface densities, and volume density was calculated. The results of this research show a competitive behavior between nucleation sites and eutectic undercooling. Higher nucleation sites and higher eutectic undercooling cause higher eutectic cell density. But increasing nucleation sites by introducing inoculants to molten metal, is accompanied with reduction in eutectic undercooling. It means that inoculation and undercooling have opposite effect on each other. So, to achieve maximum cell density, it is necessary to create an optimization between these parameters.

Słowa kluczowe

EN

cast iron; competitive nucleation; undercooling; cooling curve; grain refining

PL

żeliwo; nukleacja; przechłodzenie; krzywa krzepnięcia; rozdrabnianie ziarna

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2017
• Tom: Vol. 17, iss. 4
• Strony: 185--189
• Opis fizyczny: Bibliogr. 18 poz., rys., tab., wykr.

Twórcy

autor

Arab N.

• Department of Material Science, Islamic Azad University, Saveh Branch, Saveh, Iran

Bibliografia

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• [12] Elliot, R. (1983). Eutectic Solidification Processing. Butterworths and Co. Ltd. London.
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• [14] Thorgrimsson, J.T., Fredriksson, H., Swenson, I.L. (1987). Solidification Process of Flake Cast Iron Castings. In J. Beech and H. Jones Editor. Solidification Processing. Institute of Metals, London.
• [15] Basutkar, P., Yew, S. & Lopper. E. “Effect of Certain Additions to the Melt on the As-Cast Dendritic Microstructure of Gray Cast Iron. AFS Tran. 77(1).
• [16] Clybe, T. & Kurz, W. (1981). Solute Redistribution during Solidification with Rapid Solid State Diffusion. Met. Tran. A, 12.
• [17] Underwood E.F. Editors. (1985). Metals Handbook, Vol. 9, p. 123-124, ASM, 8th Edition.
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Uwagi

PL

Opracowanie ze środków MNiSW w ramach umowy 812/P-DUN/2016 na działalność upowszechniającą naukę (zadania 2017).