Effect of Cooling Rate on Microstructure of Thin-Walled Vermicular Graphite Iron Castings

• Autorzy: Górny M. , Kawalec M. , Sikora G.
• Języki publikacji: EN

Abstrakty

EN

This article addresses the effect of cooling rate and of titanium additions on the microstructure of thin-walled vermicular graphite iron (TWCI) castings as determined by changing molding media, section size and Ferro Titanium. The research work was carried out on TWCI castings and reference castings of 2-5 mm and 13-mm wall thickness, respectively. Various molding materials were employed (silica sand and insulating sand ‘‘LDASC’’) to achieve different cooling rates. Thermal analysis was implemented for determinations of the actual cooling rates at the onset of solidification. This study shows that the cooling rates exhibited in the TWCI castings varies widely (70- 14oC/s) when the wall thickness is changed from 2 to 5 mm. In turn, this is accompanied by a significant variation in the vermicular graphite fraction. The resultant cooling rates were effectively reduced by applying an insulating sand in order to obtain the desired vermicular graphite shape. In addition, good agreement was found between the theoretical predictions of the solidification process and the experimental outcome. Ti additions in combination with LDASC sand molds were highly effective in promoting the development of over 80 % vermicular graphite in castings with wall thicknesses of 2 and 3 mm as evidenced by quantitative metallographic analyses.

Słowa kluczowe

EN

innovative foundry technologies; innovative materials; vermicular graphite cast iron; cooling rate; thermal analysis; microstructure

PL

innowacyjne technologie odlewnicze; materiały innowacyjne; żeliwo grafitowe wermikularne; chłodzenie; analiza termiczna; mikrostruktura

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2014
• Tom: Vol. 14, iss. 1 spec.
• Strony: 139--142
• Opis fizyczny: Bibliogr. 12 poz., rys., tab., wykr.

Twórcy

autor

Górny M.

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

autor

Kawalec M.

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

autor

Sikora G.

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

Bibliografia

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• [9] Górny, M., Kawalec, M. (2013). Role of titanium in thin wall vermicular graphite iron casting production. Archives of Foundry Engineering. 13 (2/2013), 25–28.
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