The effect of cooling rate on the microstructure of nodular cast iron

• Autorzy: Binczyk F. , Kowalski A. , Futmanek J.
• Języki publikacji: EN

Abstrakty

EN

The study gives the results of the investigations concerning an effect of the casting cooling rate ( casting made from nodular iron used as a starting material for austempering to produce ADI) on the morphology of nodular graphite and metallic matrix composition. The features of the microstructure morphology were determined on a LUCIA computer program using castings of 10, 20, 40 and 60 mm diameter. It has been proved that increasing the casting diameter from 10 to 60 mm (i.e. reducing the cooling rate) increases the content of graphite from 10 to 12% and an average area of the precipitations from about 150 to 440 [mikro]m2, while it reduces the number of the graphite precipitations in 1 mm2 from about 700 to 260, the mean value of the shape factor from 0,96 to 0,84, and pearlite content in the matrix from about 96% to 84% The chemical composition seems to have no significant effect, the only exception being Mo whose presence increases in a visible way pearlite content in the matrix at each cooling rate. The obtained results, and specifically the distribution of the frequencies of occurrence of the examined morphological features of graphite, confirm the vast possibilities that the LUCIA computer program of image analysis offers in evaluation of the effect of technological parameters on cast iron microstructure.

Słowa kluczowe

EN

casting processes; cooling rate; microstructure; pearlite; graphite; circularity

PL

procesy odlewnicze; prędkość chłodzenia; mikrostruktura; perlit

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2007
• Tom: Vol. 7, iss. 2
• Strony: 115--118
• Opis fizyczny: Bibliogr. 7 poz., rys., tab.

Twórcy

autor

Binczyk F.

autor

Kowalski A.

autor

Futmanek J.

• Chair of Metal Alloys and Composites Engineering, Silesian University of Technology, Krasińskiego Str. 8, 40-019 Katowice,

Bibliografia

• [1] J. Tybulczuk, A. Kowalski, Characteristic of ADI with additions of 1,5% Ni and 0,8% Cu, Foundry Research Institute, Vol. XLVII, No. 4, (1997), 403-440
• [2] E. Guzik, Some selected problems concerning the processes of cast iron improvement, Archives of Foundry, No. 1M., (2001), (in Polish)
• [3] D. Myszka, Structural research of direct austempered ductile irons obtained in sand mould, Archives of Foundry, Vol. 1, No. 1(2/2), (2001), 263-270, (in Polish)
• [4] L. Jincheng, R. Elliot, The influence of cast structure on the austempering of ductile iron, Int. J. Cast Metals Res., 11, (1999), 407-412
• [5] L. Jincheng, R. Elliot, The role of nodule count on the kinetics, microstructure and mechanical properties of austempered Mn alloyed ductile iron, Int. J. Cast Metals Res., 12, (1999), 189-195
• [6] C. Podrzucki, Cast iron, ZG STOP, Cracow, (1991), (in Polish)
• [7] E. Fraś, Crystallization of metals, WNT, Warsaw, (2003), (in Polish)