Effects of bismuth on the matrix structure of ductile iron castings
- 1 University of Zagreb, Faculty of Metallurgy, Sisak, Croatia
Abstract
This paper deals with the effects of the addition of 0.00031, 0.00064, 0.001 and 0.0042 wt.% Bi on the matrix structure of ductile iron castings consisting of 7 sections of different thicknesses (3, 12, 25, 38, 50, 75 and 100 mm) and contain low content of Si (2.11 wt.%) and pearlite promoting element (0.018 wt.% Cu, 0.0055 wt.% Sn, 0.00041 wt.% Sb, 0.098 wt.% Mn). The Bi contents of 0.00031, 0.00064 and 0.001 wt.% were not significantly affected the share of ferrite and pearlite in the section thicknesses of 12, 25, 38, 50, 75 and 100 mm compared to the casting which does not contain Bi. In all these sections the share of pearlite was increased and the share of ferrite was decreased by the addition of 0.0042 wt.% Bi. All of the above-mentioned Bi contents were resulted in the formation of iron carbides in the section thickness of 3 mm. The share of carbides increases with increasing Bi content.
Keywords
References
- M. Gagné, The Sorelmetal Book of Ductile Iron, Rio Tinto Iron & Titanium, Montreal, Canada, 2004.
- …, Ductile Iron Handbook, ed. W. A. Henning, J. Mercer, American Foundry Society, Inc., Illinois, 2010.
- …, Ductile Iron Data for Design Engineers, Rio Tinto Iron & Titanium, Montreal, Canada, 1998.
- R.A. Gonzaga, Influence of Ferrite and Pearlite Content on Mechanical Properties of Ductile Cast Irons, Materials Science and Engineering A 567(2013), 1 – 8.
- R.A. Gonzaga, P. Martínez Landa, A. Perez, P. Villanueva, Mechanical Properties Dependency of the Pearlite Content of Ductile Irons, Journal of Achievements in Materials and Manufacturing Engineering 33(2009) 2, 150 – 158.
- P. Ferro, P. Lazzarin, F. Berto, Fatigue Properties of Ductile Iron Containing Chunky Graphite, Materials Science and Engineering A 554(2012), 122 – 128.
- I. Riposan, M. Chisamera, A. Stan, Control of Surface Graphite Degeneration in Ductile Iron for Windmill Applications, International Journal of Metalcasting 7(2013) 1, 9 – 20.
- C. Labrecque, P.M. Cabanne, Low Temperature Impact Strength of Heavy Section Ductile Iron Castings: Effect of Microstructure and Chemical Composition, China Foundry 8(2011) 1, 66 – 73.
- X. Guo, D.M. Stefanescu, Solid Phase Transformation in Ductile Iron – A Benchmark for Computational Simulation of Microstructure, AFS Transactions 105(1997), 533 - 543.
- D. Venugopalan, A Kinetic Model of the γ →α + Gr Eutectoid Transformation in Spheroidal Graphite Cast Irons, Metallurgical Transactions A 21(1990) 4, 913 - 918.
- H. Morrogh, Influence of some residual elements and their neutralisation in magnesium treated nodular cast iron, AFS Transactions 60 (1952), 439 – 452.
- G.S. Cole, Solidification of Ductile Iron, AFS Transactions 80 (1972), 335 - 348.
- P. Ferro, A. Fabrizi, R. Cervo, C. Carollo, Effect of Inoculants Containing Rare Earth Metals and Bismuth on Microstructure and Mechanical Properties of Heavy-Section Near-Eutectic Ductile Iron Castings, Journal of Materials Processing Technology 213(2013) 9, 1601 – 1608.
- H. Horie, T. Kowata, A. Chida, Influence of Bismuth on Graphite Nodule Count in Thin-section Spheroidal-graphite Cast Iron, Cast Metals, 2(1990) 4, 197 - 202.
- H. Takeda, H. Yoneda, K. Asano Effect of Silicon and Bismuth on Solidification Structure of Thin Wall Spheroidal Graphite Cast Iron, Materials Transactions 51(2010) 1, 176 – 185.
- F. Unkić, Z. Glavaš, K. Terzić, Utjecaj broja nodula na žilavost feritnog nodularnog lijeva, Strojarstvo: časopis za teoriju i praksu u strojarstvu 50(2008) 4, 231-238.
- Z. Glavas, A. Strkalj, K. Maldini, F. Kozina, Effect of Bismuth and Rare Earth Elements on Graphite Structure in Different Section Thicknesses of Spheroidal Graphite Cast Iron Castings, Archives of Metallurgy and Materials 63(2018) 3, 1547-1553.
- I. Riposan, M. Chisamera, A. Stan, Control of Surface Graphite Degeneration in Ductile Iron for Windmill Applications, International Journal of Metalcasting 7(2013) 1, 9 – 20.
- I. Riposan, M. Chisamera, V. Uta, S. Stan, The Importance of Rare Earth Contribution From Nodulizing Alloys and Their Subsequent Effect on the Inoculation of Ductile Iron, International Journal of Metalcasting 8(2014) 2, 65 – 80.
- I. Riposan, M. Chisamera, S. Stan, Performance of Heavy Ductile Iron Castings for Windmills, China Foundry 7(2010) 2, 163 - 170.
- A. Javaid, C. R. Loper, Jr., Production of Heavy-Section Ductile Cast Iron, AFS Transactions 103(1995), 135 – 150.
- E.N. Pan, C. Y. Chen, Effects of Bi and Sb on graphite structure of heavy-section ductile cast iron, ASF Transaction 104(1996), 845 – 858.
- I. Riposan, M. Chisamera, S. Stan, Influencing Factors on Ascast and Heat Treated 400-18 Ductile Iron Grade Characteristics, China Foundry 4(2007) 4, 300 - 303.