Solidification conditions of gray and white cast iron. Part I - Theoretical background

• Autorzy: Fraś E. , Górny M. , Lopez H.F.

Warianty tytułu

PL

Warunki krystalizacji żeliwa szarego i białego. Część I - Analiza teoretyczna

• Języki publikacji: EN

Abstrakty

EN

The present work is based on a heat balance during the solidification of cast iron. Accordingly, an analytical expression was derived to relate the chilling tendency (CT) of cast iron with nucleation and growth processes associated with eutectic graphite and cementite constituents. A relationship is found between the CT and factors such as the physical-chemical state of liquid, the distribution of nucleation sites, and the density of nucleation sites for eutectic grains. In particular, it is found that the casting modulus (M), enabling determinations of minimum wall thickness for chilled castings or chill widths in wedge shaped castings can be related to the CT. Finally, the present work provides a rationatization for the effect of technological factors such as the chemistry of the melt, inoculation practice, holding temperature and time on the resultant CT and chill of the cast iron.

PL

Na podstawie bilansu ciepła podczas krystalizacji żeliwa wyprowadzono równanie, które wiąże skłonność żeliwa do krystalizacji eutektyki cementytowej (skłonność do zabieleń CT) z procesem zarodkowania i wzrostu eutektyki grafitowej oraz cementytowej. Znaleziono zależność pomiędzy CT i takimi czynnikami, jak fizykochemiczny stan ciekłego metalu, rozkład i gęstość miejsc do zarodkowania. W szczególności wykazano, że moduł odlewu M, przy którym krystalizuje eutektyka cementytowa i szerokość zabielenia klina, zależą od CT. Podano również wpływ czynników technologicznych, to jest składu chemicznego kąpieli, praktyki modyfikowania, a także czasu i temperatury wytrzymywania kąpieli na skłonność żeliwa do zabieleń CT oraz na zabielenia.

Słowa kluczowe

EN

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

PL

zabielenia; skłonność żeliwa do zabieleń; eutektyka grafitowa; eutektyka cementytowa; żeliwo

• Wydawca: AGH University of Science and Technology Press
• Czasopismo: Metallurgy and Foundry Engineering
• Rocznik: 2005
• Tom: Vol. 31, No 1
• Strony: 13--35
• Opis fizyczny: Bibliogr. 30 poz., rys., tab., wykr.

Twórcy

autor

Fraś E.

• Faculty of Foundry Engineering, AGH University of Science and Technology, Reymonta 23, 30-059 Kraków

autor

Górny M.

• Faculty of Foundry Engineering, AGH University of Science and Technology, Reymonta 23, 30-059 Kraków

autor

Lopez H.F.

• Department of Materials Engineering, University of Wisconsin-Milwaukee

Bibliografia

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