Abstract
The purpose of this study was to determine the impact of niobium addition as an inoculation element on the microstructure and electrochemical properties of EN-FGL250 gray cast iron. Niobium additions are in a powder form and have a 0.5 mm particle size at dfferent proportions of 1wt.% and 3wt.%. The addition was done during casting of the metal in the mold at the last cooling step of the melt cast iron. These additions have a significant impact on the phenomenon of solidification as the metal powder deposited in the sand molds creates new centers of germination and absorbs a lot of heat. The cooling rate directly affects the microstructure and electrochemical behavior. This is confirmed by SEM observations and electrochemical tests. Furthermore, the addition of niobium transforms the microstructure of gray cast iron from cellular structure into totally dendritic structure. As a consequence, the niobium addition affected the shape and size of graphite, thus considerably reducing the corrosion current density by increasing the polarization resistance Rp.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Balachandran G, Vadiraj A, Kamaraj M, Kazuya E. Mechanical and wear behavior of alloyed gray cast iron in the quenched and tempered and austempered conditions. Materials & Design, 2011, 32 (7): 4042–4049.
de Almeida L H, Ribeiro A F, Le May I. Microstructuralcharacterization of modified 25Cr–35Ni centrifugally cast steel furnace tubes. Materials Characterization, 2002, 49 (3): 219–229.
Kesri R, Durand-Charre M. Phase equilibria, solidification and solid-state transformations of white cast irons containing niobium. Journal of Materials Science, 1987, 22 (8): 2959–2964.
Filipovic M, Kamberovic Z, Korac M, Gavrilovski M. Microstructure and mechanical properties of Fe-Cr-C-Nb white cast irons. Materials & Design, 2013, 47: 41–48.
Alonso G, Stefanescu D, Larra˜naga P, et al. Solidification of superfine graphite iron revealed by interrupted solidification experiments. International Journal of Cast Metals Research, 2016, 29 (5): 258–265.
Riposan I, Chisamera M, Stan S, et al. A new approach to graphite nucleation mechanism in gray irons. In Proceedings of the AFS Cast Iron Inoculation Conference, September 2005: 29–30.
Lunarska E. Effect of graphite shape on the corrosion of grey cast iron in phosphoric acid. Materials and Corrosion, 1996, 47 (10): 539–544.
Gelfi M, Gorini D, Pola A, et al. Effect of titanium on the mechanical properties and microstructure of gray cast iron for automotive applications. Journal of Materials Engineering and Performance, 2016, 25 (9): 3896–3903.
Davis J R, Ed., ASM Specialty Handbook-Stainless Steels. ASM International, 1994.
Collini L, Nicoletto G, Konecna R. Microstructure and mechanical properties of pearlitic gray cast iron. Materials Science and Engineering: A, 2008, 488 (1): 529–539.
Murakami T, Inoue T, Shimura H, et al. Damping and tribological properties of Fe-Si-C cast iron prepared using various heat treatments. Materials Science and Engineering A, 2006, 432 (1): 113–119.
Riposan I, Chisamera M, Stan S, et al. Three-stage model for nucleation of graphite in grey cast iron. Materials Science and Technology, 2010, 26 (12): 1439–1447.
Riposan I, Chisamera M, Stan S, et al. Role of lanthanum in graphite nucleation in grey cast iron. Key Engineering Materials, Trans Tech Publ, 2011, 457: 19–24.
Moumeni E, Stefanescu D M, Tiedje N S, et al. Investigation on the effect of sulfur and titaniumon the microstructure of lamellar graphite iron. Metallurgical and Materials Transactions A, 2013, 44 (11): 5134–5146.
Sommerfeld A, Tonn B. Nucleation of graphite in cast iron melts depending on manganese, sulphur and oxygen. International Journal of Cast Metals Research, 2008, 21(1-4): 23–26.
Muhmond H M, Fredriksson H. Relationship between inoculants and the morphologies of MnS and graphite in gray cast iron. Metallurgical and Materials Transactions B, 2013, 44 (2): 283–298.
Goodrich G, Oakwood T, Gundlach R. Manganese, sulfur and manganese-sulfur ratio effects in gray cast iron. Transactions of the American Foundry Society and the One Hundred Seventh Annual Castings Congress, 2003: 783–812.
Fra´s E, G´orny M. Mechanism of dissolved sulfur influence on the transition from graphite to cementite eutectic in cast iron. Key Engineering Materials, Trans Tech Publ, 2011, 457: 137–142.
Mehra R, Soni A. Cast iron deterioration with time in various aqueous salt solutions. Bulletin of Materials Science, 2002, 25 (1): 53–58.
Seidu S O, Owoeye S S, Owoyemi H T. Assessing the effect of copper additions on the corrosion behaviour of grey cast iron. Leonardo Electronic Journal of Practices and Technologies, 2015, 26: 49–58.
Jami R I, Litin A K S. Inhibition of the pitting corrosion of grey cast iron using carbonate. Materiali in Tehnologije, 2006, 40 (1): 3.
Saricimen H, Quddus A, Eid O A, et al. Corrosion behaviour of cast iron exposed to Arabian gulf environment. Anti-Corrosion Methods and Materials, 2011, 58 (6): 303–311.
Atkinson K, Whiter J, Smith P, et al. Failure of small diameter cast iron pipes. Urban Water, 2002, 4 (3): 263–271.
Yamamoto K, Mizoguti S, Nagano S, et al. Service life prediction of industrial pipe-line. Tetsu-to-Hagane, 1985, 71 (1): 121–126.
Mohebbi H, Li C Q. Experimental investigation on corrosion of cast iron pipes. International Journal of Corrosion, 2011, Article ID 506501.
Tronstad L, Sejersted J. The effect of sulphur and phosphorus on the corrosion of iron. Journal of the Iron and Steel Institute, 1933, 127: 425–436.
Miyata Y, Kuwahara Y, Asakura S, et al. Anodic dissolution of spheroidal graphite castiron with different pearlite areas in sulfuric acid solutions. International Journal of Corrosion, 2013, Article ID741378.
Behnam M J, Davami P, Varahram N. Effect of coolingrate on microstructure and mechanical properties of gray castiron. Materials Science and Engineering A, 2010, 528 (2): 583–588.
Fràs E, G´orny M, Lopez H. Eutectic cell and nodule count in grey and nodular cast irons. Materials Science and Technology, 2007, 23 (9): 1109–1117.
Mizoguchi T, Perepezko J. Nucleation behavior during solidification of cast iron at high undercooling. Materials Science and Engineering A, 1997, 226: 813–817.
Pedersen K M, Tiedje N S. Undercooling and nodulecount in thin walled ductile iron castings. International Journal of Cast Metals Research, 2007, 20 (3):145–150.
Riposan I, Chisamera M, Stan S, et al. Graphite nucleant(microinclusion) characterization in Ca/Sr inoculated grey irons. International Journal of Cast Metals Research, 2003, 16 (1-3): 105–111.
Zhou Jiyang. Colour Metallography of Cast Iron. China Foundry, 2009, 6 (1): 57–69.
Kawalec M, G´orny M. Alloyed white cast iron with precipitates of spheroidal vanadium carbides VC. Archives of Foundry Engineering, 2012, 12 (4): 95–100.
Kiani-Rashid A R, Mostafapour M, Kaboli-Mallak S K, Babakhani A. The effect of cooling rate on bainite phase formation in austempered nickel-molybdenum gray cast iron. ISRN Materials Science, 2011, 2011, Article ID 923241.
Chisamera M, Riposan I, Stan S, et al. Graphite nucleation control in grey cast iron. International Journal of Cast Metals Research, 2008, 21(1-4): 39–44.
Park J, Verhoeven J. Transitions between type a flake, type D flake, and coral graphite eutectic structures in cast irons. Metallurgical and Materials Transactions A, 1996, 27 (9): 2740–2753.
Nakae H, Fujimoto K. Influence of Ti on graphite morphological transition in flake graphite cast iron. Key Engineering Materials, Trans Tech Publ, 2011, 457: 25–30.
Okada A, Miyake H. The unknown world of cast iron. KANSAI Univ Press, 1996: 141.
Zhi X, Xing J, Fu H, et al. Effect of niobium on the as-cast microstructure of hypereutectic high chromium cast iron. Materials Letters, 2008, 62 (6): 857–860.
Zhou Wenbin, Zhu Hongbo, Zheng Dengke, et al. Niobium alloying effect in high carbon equivalent grey cast iron. Research & Development, 2011: 36–40.
Zumelzu E, Cabezas C, Opitz O, et al. Microstructural characteristics and corrosion behaviour of high-chromium cast iron alloys in sugar media. Protection of Metals, 2003, 39 (2): 183–188.
Vasudevan S, Raja V, Seshan S, Chattopadhyay K. Study of influence of manganese additions on electrochemical corrosion behaviour of austenitic spheroidal graphite iron. British Corrosion Journal, 1986, 21(2): 87–94.
Azim A A, Sanad S. Effects of acid concentration, content and temperature on the corrosion rate of steel in HCl. Corrosion Science, 1972, 12 (4): 313–324.
Fontana M G. Corrosion Engineering. Tata McGraw-Hill Education, 2005.
Author information
Authors and Affiliations
Corresponding author
Additional information
Male, born in 1979, Teacher (assistant master) at University of Sciences and Technology Houari Boumedienne Algiers, Algeria, also Ph.D student in Materials Science and Engineering. He is currently working on the development of a surface treatment process for gray cast irons directly in the manufacturing stage of parts without resorting to conventional (physical or chemical) surface treatments by metal deposition process or surface treatment. The influence of additions in the gray cast iron of various metallic materials, especially those of the fifth and sixth columns of the periodic table, is also part of the his research work field of interest. He is interested in the impact that these elements can have on the microstructure, mechanical and chemical change of gray cast iron.
Rights and permissions
About this article
Cite this article
Azzoug, M.O., Boutarek-Zaourar, N., Aboudi, D. et al. Niobium addition effect in molds at last cooling step on EN-GJL250 gray cast iron: Microstructural changes and electrochemical behavior. China Foundry 15, 228–235 (2018). https://doi.org/10.1007/s41230-018-8007-4
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s41230-018-8007-4