ÖSTENİTLEME SICAKLIĞININ EN-GJS-600-3 KÜRESEL GRAFİTLİ DÖKME DEMİRİN ÖSTEMPERLENME DAVRANIŞINA ETKİLERİNİN ARAŞTIRILMASI

Year 2020, Volume: 8 Issue: 3, 706 - 722, 03.09.2020

Erkan Konca Kazım Tur

https://doi.org/10.36306/konjes.705209

Cited By: 1

Abstract

Bu çalışmada östenitleme sıcaklığının EN-GJS-600-3 (GGG-60) küresel grafitli dökme demirin
östemperlenme davranışına etkisi araştırılmıştır. Y bloklarına dökülen % 0,5 Cu alaşımlı EN-GJS-600-3
küresel grafitli dökme demirden çıkarılan numuneler kullanılarak iki farklı östenitleme sıcaklığı (850 ve
950°C) ve iki farklı östemperleme sıcaklığının (290 ve 320°C) dört ayrı kombinasyonunda östemperleme
deneyleri yapılmıştır. Östemperleme deneyleri sonrası numunelerin sertlik ölçümleri, çekme testleri ve iç
yapı incelemeleri gerçekleştirilmiştir. Her iki östemperleme sıcaklığında da 950°C’de östenitlenmiş
numunelerde 850°C’de östenitlenmiş numunelere göre daha yüksek sertlik, akma ve çekme dayanımı
değerlerine ulaşılmıştır. Bu sonuçlar, 950°C’de yapılan östenitlemenin 850°C’ye göre östenit matris içinde
hem daha çok karbonun çözünmesini hem de östenitin daha iri taneli olmasını sağlayarak
östemperlenmeye daha elverişli östenit yapısı oluşturabilmesiyle ilişkilendirilmiştir.

Keywords

EN-GJS-600-3, östemperleme, östemperlenmiş sünek dökme demir, ösnitleme, östenitleme sıcaklığı, östenit karbon içeriği, östenit tane boyutu, segregasyon

Thanks

EN-GJS-600-3 alaşımından Y blokların döküldüğü Ekstrametal Döküm İzaba ve Mak. San. Tic. Ltd. Şti’ne, metalografik numune hazırlıkları için Özdemir Dinç’e, sertlik ölçümleri için Yaşar Kazanç’a ve çekme testleri için Erkin Koç’a teşekkür ederiz.

Investigation of the Effects of Austenitizing Temperature on the Austempering Behavior of EN-GJS- 600-3 Spheroidal Graphite Cast Iron

Abstract

The effect of austenitizing temperature on the austempering behavior of EN-GJS-600-3
(GGG-60) spheroidal graphite cast iron was investigated. 0.5% Cu alloyed EN-GJS-600-3 spheroidal
graphite cast iron samples obtained from Y-blocks were subjected to four different austempering
experiments as a combination of two different austenitizing (850 and 950°C) and two different
austempering temperatures (290 and 320°C). Hardness measurements, tensile tests and microstructural
examinations were performed after the austempering experiments. The samples austenitized at 950°C
produced higher hardness, yield and tensile strength values as compared to the samples austenitized at
850°C. This observation was linked to the fact that as compared to 850°C austenitizing at 950°C provided
both more carbon to dissolve in the austenite matrix and larger austenite grain size resulting in better
austemperability.

Keywords

EN-GJS-600-3, austempering, austempered ductile iron, austenitizing, austenitizing temperature, austenite carbon content, austenite grain size, segregation

References

• Akbarzadeh C.E., Iranipour, N., Yazdani, S., 2016, “Effect of nodule count and austempering heat treatment on segregation behavior of alloying elements in ductile cast iron”, China Foundry, 13, 217-222. https://doi.org/10.1007/s41230-016-6034-6,
• ASTM A897/A897M—03 Standard Specification for Austempered Ductile Iron Castings; ASTM International: West Conshohocken, PA, USA, 2003.
• Batra U., Ray S., Prabhakar S.R., 2003, “Effect of Austenitization on Austempering of Copper Alloyed Ductile Iron, Journal of Materials Engineering and Performance”, 12 (5), 597-601, https://doi.org/10.1361/105994903100277120
• Bayati H., Elliot R., 1995, “Austempering process in high manganese alloyed ductile cast iron”, Materials Science and Technology, 11 (2), 118-130.
• Bayati, H., Elliott, R., 1999, “The Concept of an Austempered Heat Treatment Processing Window”, International Journal of Cast Metals Research, 11:5, 413-417, DOI: 10.1080/13640461.1999.11819309
• Bazhenov V.E., Pikunov M.V. 2018, “Microsegregation of Silicon in Cast Iron”, Izvestiya. Ferrous Metallurgy, 61(3):230-236. (Rusça) https://doi.org/10.17073/0368-0797-2018-3-230-236
• Boneti L.L.T., Hupalo M.F., Junior S.V., Rosário A.M., 2017, “Influence of casting heterogeneities on microstructure and mechanical properties of austempered ductile iron (ADI)”, Revista Materia, 22 (3), 11858. DOI: 10.1590/S1517-707620170003.0192
• BSI (British Standards Institution). EN 1564:2011 Founding—Ausferritic Spheroidal Graphite Cast Irons; BSI:London, UK, 2011.
• Chang L.C., 2003, “An Analysis of Retained Austenite in Austempered Ductile Iron”, Metallurgical and Materials Transactions A, 34A (2), 211-217.
• Eric O., Brdaric T., Stojsavljevic N., Tonic M., Grahovac N., Duricic R., 2010, “Determination of Processing Window for ADI Materials Alloyed with Copper”, MJoM, Metallurgical and Materials Engineering, 16 (2), 91-102, 2010.
• Górny M., Angella G., Tyrała E., Kawalec M., Paź S., Kmita A., 2019, “Role of Austenitization Temperature on Structure Homogeneity and Transformation Kinetics in Austempered Ductile Iron”, Metals and Materials International, 25, 956–965. https://doi.org/10.1007/s12540-019-00245-y
• Harding R. A., 2007, “The production, properties and automotive applications of austempered ductile iron”, Kovove Mater. 45, 1–16.
• Jincheng L., Elliott R., 1999, “The influence of cast structure on the austempering of ductile iron”, International Journal of Cast Metals Research, 11:5, 407-412, DOI: 10.1080/13640461.1999.11819308
• Keough J.R., Hayrynen K. L., 2000, “Automotive Applications of Austempered Ductile Iron (ADI): A Critical Review”, Journal of Materials & Manufacturing, SAE Transactions, 109 (5), 344-354.
• Konca, E., Tur, K., Koç, E. 2017, “Effects of Alloying Elements (Mo, Ni, and Cu) on the Austemperability of GGG-60 Ductile Cast Iron”, Metals, 7, 320.
• Ławrynowicz Z., Dymski S., 2007, “Carbon Concentration of Austenite in Austempered Ductile Iron (ADI)”, Arhieves of Foundry Engineering, 7 (3), 93 – 98.
• Lee, S-J., Lee, Y-K., 2008, “Prediction of austenite grain growth during austenitization of low alloy steels”, Materials and Design, 29 1840–1844, doi:10.1016/j.matdes.2008.03.009
• Lefevre J., Hayrynen K.L., 2013, “Austempered Materials for Powertrain Applications”, Journal of Materials Engineering and Performance, 22 (7), 1914-1922. DOI: 10.1007/s11665-013-0557-4
• Li, X.; Wagner, J.N.; Stark, A.; Koos, R.; Landesberger, M.; Hofmann, M.; Fan, G.; Gan, W.; Petry, W., 2019, “Carbon Redistribution Process in Austempered Ductile Iron (ADI) During Heat Treatment— APT and Synchrotron Diffraction Study”, Metals, 9, 789. https://doi.org/10.3390/met9070789
• Lin B.Y., Chen E.T., and Lei T.S., 1998, “The Effect of Segregation on the Austemper Transformation and Toughness of Ductile Irons”, Journal of Materials Engineering and Performance, 7(3), 407-419.
• Öztürk E., Yıldırım M., 2019, “Östemperleme Sıcaklık ve Süresinin Östemperlenmiş Sünek Dökme Demirlerin Mikto Yapı ve Sertliğine Etkisi”, Konya Mühendislik Bilimleri Dergisi, 7(3), 604-611. https://doi.org/10.36306/konjes.613878
• Panneerselvam, S., Martis, C.J., Putatunda, S.K., Boileau, J.M., 2015, “An investigation on the stability of austenite in Austempered Ductile Cast Iron (ADI)”, Materials Science and Engineering: A, 626, 237-246, https://doi.org/10.1016/j.msea.2014.12.038
• Porter, D.A., Easterling K.E. Phase Transformations in Metals and Alloys, 2nd Ed., Chapman & Hall, London, UK, 1992; p. 139.
• Radulovic B., Bosnjak B., Harding R., Pop-Tonev K., Asanovic V., 2000, “The Influence of Austenitising Temperature on the Microstructure and Mechanical Properties of Low-Alloyed Ni-Mo-Cu Austempered Ductıle Iron”, Mater. Tehnol., 34 (5), 207-212.
• Rasband, W., ImageJ; U.S. National Institutes of Health: Bethesda, MD, USA, 1997–2016 Rivera, G. L., Boeri, R. E., Sikora, J. A., 1995, “Revealing the solidification structure of nodular iron”, Cast Metals, 8:1, 1-5, DOI: 10.1080/09534962.1995.11819186
• Schissler J. M., Saverna J., 1985, “The Effect of Segregation on the Formation of Austempered Ductile Iron”, J. Heat Treating, 4 (2), 167-176.
• Sikora J., Boeri R., 1999, “Solid state transformations in ductile iron—influence of prior austenite matrix microstructure”, International Journal of Cast Metals Research, 11:5, 395-400, DOI: 10.1080/13640461.1999.11819306
• Solntsev, L.A., Pavlyuchenko, A.A., Minyailo, T.L. et al., 1977, Effect of alloying on austenite grain size of magnesium cast iron, Met Sci Heat Treat 19, 316–317. https://doi.org/10.1007/BF00700821
• Voigt R. C., Loper C. R., 1984, “Austempered Ductile Iron - Process Control and Quality Assurance”, J. Heat Treating, 3 (4), 291-309.