E. Üstün, E. ÇADIRLI, H. KAYA, K. KEŞLİOĞLU

DOĞRUSAL KATILAŞTIRILMIŞ SUCCİNONİTRİL-ASETON ALAŞIMININ MİKROYAPI PARAMETRELERİNİN KATILAŞTIRMA PARAMETRELERİNE BAĞLILIĞI

Succinonitril-ağ.% 3.61 Aseton organik alaşımı sabit büyütme hızında (V = 6.5 µm/s) beş farklı sıcaklık gradyenti için (G = 3.53-5.70 K/mm) ve sabit sıcaklık gradyentinde (G = 5.70 K/mm) beş farklı büyütme hızı için (V = 6.5- 113.0 µm/s) tek yönlü doğrusal olarak katılaştırılmıştır. Birincil dendrit kol mesafesi, ikincil dendrit kol mesafesi, dendrit uç yarıçapı ve yumuşak bölge derinliği ölçülmüştür. Katılaştırma parametrelerinin (G, V) değerinin artmasıyla mikroyapı parametrelerinin (λ1, λ2, R ve d) değerinin azaldığı gözlenmiştir. Elde edilen mikroyapı parametreleri ile literatürdeki deneysel sonuçlar karşılaştırılmıştır.

Anahtar Kelimeler:

Doğrusal katılaştırma, Organik bileşikler, Mikroyapı parametreleri

DEPENDENCY OF MICROSTRUCTURE PARAMETERS ON THE SOLIDIFICATION PARAMETERS IN THE DIRECTIONALY SOLIDIFIED SUCCINONITRILEACETONE ALLOY

Succinonitrile-3.61wt.% Acetone alloy was unidirectionally solidified with a constant growth rate (V = 6.5 µm/s) at five different temperature gradients (G = 3.53-5.70 K/mm) and with a constant temperature gradient (G = 5.70 K/mm) at five different growth rates (V = 6.5-113.0 µm/s). The primary dendrite arm spacings, secondary dendrite arm spacings, dendrite tip radius and mushy zone depth were measured. The values of microstructure parameters (λ1, λ2, R and d) decrease as the values of solidification parameters (G and V) increase. The obtained results for the microstructure parameters have been compared with the experimental observations, and a comparison of our results with the previous experimental results have also been made.

Keywords:

Directional solidification, Organic compounds, Microstructure parameters,

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Han, S.H., Trivedi, R., Primary Spacing selection in Directionally Solidified Alloys, Acta Metall, 42, 25-41, 1994.
Huang, W., Geying, X. and Zhou, Y., Primary Spacing Selection of Constrained Dendritic Growth, J. Cryst. Growth, 134, 105–115, 1993.
Taha, M.A., Some Observations on The Dendritic Morphology and Dendrite Arm Spacings, Metall. Science, 1, 9-12, 1979.
Grugel, R. N. and Zhou, Y., Primary Dendrite Spacing and The Effect of Off-Axis Heat Flow, Met.Trans. A, 20, 969–973, 1989.
Liu, L.X. and Kirkaldy, J.S., Systematic of Thin Film Cellular-Dendrites and The Cell to Dendrite Transition in Succinonitrile-Salol, Succinonitrile-Acetone, J. Crys. Growth, 140, 115-122, 1994.
Billia, B. , Trivedi, R., Pattern Formation in Crystal Growth, Handbook Cryst. Growth, Elsevier Science Publishers B.V.,Amsterdam, Netherlands, 918-929, 1993.
Çadırlı, E., Maraşlı, N., Bayender, B. and Gündüz, M., Dependency of the Microstructure Parameters on The Solidification Parameters for Camphene, Mat. Res. Bull., 35, 985-995, 2000.
Trivedi, R. and Somboonsuk, K., Constrained Dendritic Growth and Spacing, Mat. Sci. Eng., 65, 65-74, 1984.
Somboonsuk, K., Mason, J.T. and Trivedi, R., Interdendritic Spacings; Part1: Experimental Studies, Metallurgical Transaction A, 15, 967–975, 1984.
Esaka, H. and Kurz, W., Columnar Dendrite Growth: Experiments on Tip Growth, J. Cryst. Growth, 72, 578- 584, 1985.
Langer, J.S. and Müller-Krumbhaar, H., Sidebranching Instabilities in a Two Dimensional Model of Dendritic Solidification, Acta Metallurgica, 29, 145-157, 1980.
Çadırlı, E., Maraşlı, N., Bayender, B. and Gündüz, M., Investigation of the Structure Parameters According to the Solidification Parameters for Pivalic Acid, J. Mat. Sci., 34, 5533-5541, 1999.
Akamatsu, S., Faivre, G., Ihle, T., Symmetry-Broken Double Fingers and Seaweed Patterns in Thin-Film Directional Solidification of a Nonfaceted Cubic Crystal, Phy. Rev. E, 51, 4751-4773, 1995.
Hunt, J.D., Solidification and Casting of Metals, The Metal Society, London, 1979.
Trivedi, R., Interdendritic Spacing: Part II. A. Comparison of Theory and Experiment, Met. Trans. A., 15, 977- 982, 1984.
Kurz, W., Fisher, D.J., Dendritic Growth and Limit of Stability Tip Radius and Spacing, Acta Metall., 29, 11- 20, 1981.