Behaviour of oxygen in cast irons

• Autorzy: Elbel T. , Senberger J. , Zadera A. , Hampl J.
• Języki publikacji: EN

Abstrakty

EN

Purpose: Cast irons are the basic structural material and they form 75% of the world production of castings. The crystallization of cast iron and the formation of graphite are a complex process influencing by oxygen. The aim of our study is to identify the role of oxygen in Fe-C-Si melts. Design/methodology/approach: Continuous comparison of changes in metal composition and oxygen activity during melting, pouring, and solidification of experimental castings, using metallographic methods and microanalysis. Determination of total oxygen content in cast iron by the high temperature extraction method. Findings: Oxygen activity in graphitic cast irons is determined during manufacture of liquid metal and its pouring mainly by carbon and silicon activities. Silicon deoxidates cast irons at lower temperatures, at higher temperatures this function is taken over by carbon. Logarithmic dependences of oxygen activity on temperature for individual graphite forms (lamellar, vermicular, and spheroidal ones) have been obtained. Determination of total oxygen content in cast iron on the other hand gives valuable information for controlling surface and internal quality of cast irons. Practical implications: Possibility of control the cast iron structure and graphitization during crystallization by monitoring the oxygen content with an indirect method of oxygen activity measurement in the melt before metal pouring the mould. Originality/value: The used method gives reproducible results which are comparable under different conditions of metal melting and pouring. Obtained knowledge extends the understanding in the field of cast irons crystallization by less known influence of oxygen.

Słowa kluczowe

EN

casting; oxygen; cast iron; graphite morphology

PL

odlewanie; tlen; żeliwo; morfologia grafitu

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2008
• Tom: Vol. 33, nr 2
• Strony: 111--116
• Opis fizyczny: Bibliogr. 15 poz.

Twórcy

autor

Elbel T.

autor

Senberger J.

autor

Zadera A.

autor

Hampl J.

• Department of Foundry Engineering, VSB-Technical University of Ostrava, 708 33 Ostrava-Poruba, Czech Republic,

Bibliografia

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