Mechanism of carbon influence on the transition from graphite to cementite eutectic in cast iron

• Autorzy: Fraś E. , Górny M.
• Języki publikacji: EN

Abstrakty

EN

In this work an analytical solution is used to explain mechanism of carbon influence on the transition from graphite to cementite eutectic in cast iron. It is found that this transition can be related to (1) the nucleation potential of graphite (characterized directly by the cell count, N and indirectly by nucleation coefficients N_s and b) (2) the growth rate coefficient of graphite eutectic cell, [mi] (3) the temperature range, [delta]T_sc = T_s - T_c (where T_s and T_c is the equilibrium temperature of the graphite eutectic and formation temperature of the cementite eutectic respectively) and (4) the liquid volume fraction, f_l after solidification of the pre-eutectic austenite. Method of estimation of N_s b and [mi] values was presented. It has been shown that the main impact of carbon on the transition from graphite to cementite eutectic consist in increasing the eutectic cell count and growth rate of graphite eutectic cell. Analytical equations were derived to describe the absolute, CT relative chilling tendency, CTr and chill, w of cast iron.

Słowa kluczowe

EN

cast iron; graphite eutectic; cementite eutectic; chilling tendency; chill; foundry processes

PL

żeliwo; grafit; węgiel; cementyt eutektyczny; chłodzenie; odlewnictwo

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2010
• Tom: Vol. 10, iss. 2
• Strony: 51--56
• Opis fizyczny: Bibliogr. 11 poz., rys., tab., wykr.

Twórcy

autor

Fraś E.

• AGH – University of Science and Technology, Reymonta 23, 30-059 Kraków, Poland

autor

Górny M.

• AGH – University of Science and Technology, Reymonta 23, 30-059 Kraków, Poland

Bibliografia

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• [6] Fraś E., Wiencek K., Górny M., Lopez H.: Graphite nodule and eutectic cell count in cast iron; Theoretical model based on Weibull statistics and experimental verification, Metallurgical and Material Transctions A, vol. 38A, 385-395, (2007).
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• [10] Fraś E., Górny M., Lopez H.: The Transition from Gray to White Iron during Solidification, Metallurgical Transactions and Materials, Part I Theoretical background, vol. 36A, 3075-3082, (2005).
• [11] Fraś E., Górny M., Lopez H.: The Transition from Gray to White Iron during Solidification; Part II Experimental verification, Metallurgical Transactions and Materials, vol. 36A, 3083-3092, (2005).