Abstract
This paper presents some data on the microstructural features and mechanical properties of as-cast compacted graphite iron (CGI), produced through treatment with a special Ca-CaC2-Mg masteralloy. Information on graphite morphology and matrix features, obtained using different numerical indices evaluated through a computer-based image-analyzing system and SEM observation of deep-etched specimens, shows that the graphite form is a mixture of ASTM types I, II, and III (compacted graphite), interspersed in a matrix with a 2:1 ratio of pearlite to ferrite. An average hardness (BHN) of 219, Charpy-V-Impact energy of 7.92 J, tensile strength of 354.5 MPa, and a corresponding elongation of 1.20% has been obtained for the as-cast iron. The fracture surfaces of tensile and room temperature impact tested specimens showed mixed modes of fracture.
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References
Anon: “Cast Iron Grades,” Guldsmedshytte Bruks AB, http://www.guldsmedshyttebruk.se/eng/castiron_grades.htm (8 Aug 2002).
CSD: “Tech. Articles. Mechanical Properties of Compacted Graphite Iron,” http://www.castingsource.com/tech_art_graphite.asp (8 Aug 2002).
Anon: “Compacted Graphite Iron, Technical Data,” I. H. Dick & Co. Ltd., http://www.thdick.co.uk/ductile.htm (8 Aug 2002).
H. Wong: “Techniques Being Developed to Produce High Strength, Lighter Weight Automobile Castings,” Metal Casting, http://www.oit.doe.gov/IOF/metalcast/ (8 Aug 2002).
G.S. Vasilash: “Material Driving Powertrain Production: Compacted Graphite Iron,” http://www.autofieldguide.com/columns/gary/0102mat.html (8 Aug 2002).
G. Georgiou: “Machining Solutions for Compacted Graphite Iron,” Machine Shop Guide Web Archive — Jan/Feb. 2002, http://www.machineshopguide.com/pdf/Jan02/compact.pdf (8 Aug 2002).
Ford Motor Company: “Ford to Introduce Compacted Graphite Iron (CGI) Cylinder Block,” http://www.dieselnet.com/news/0107ford.html, 2001 (8 Aug 2002).
Anon: “Ductile Iron News, Intermet Leads Joint Development of Enhanced Compacted Graphite Iron,” http://www.ductile.org/magazine/1999_1/compacted.htm, 1999 (8 Aug 2002).
Anon: “Tupy Noticias On Line, Ford Selects Tupy and SinterCast for New Engine Programme,” http://www.tupy.com.br/ing/pagina_news_29_06_2001i.htm, 2001 (8 Aug 2002).
R. Elliott: “An Introduction to Cast Irons” in Cast Iron Technology, Butterworths, London, 1988, pp. 20–24.
F.A. Mountford: “The Influence of Nitrogen on the Soundness and Structure of Grey Cast Iron,” Brit. Foundryman, 1966, 59, p. 141.
M.A. Rice, A.B. Malizo, and H.F. Brooks: “The Use of Multiple Nodularizing Elements in Making Ductile Iron Pipe,” Trans. Am. Foundrymen’s Soc., 1974, 82, pp. 15–26.
Anon: “Compacted Graphite Iron, Tech. Info. 13, Revision No. 2,” Elkem ASA, Silicon Division, Oslo, Norway, Mar 1997.
B.I. Imasogie, J.A. Ali, and A.A. Afonja: “Properties of Ductile Cast Iron Nodularised with Multiple Calcium-Magnesium Based Master Alloy,” Mater. Sci. Technol., 2000, 16(2), pp. 194–201.
B.I. Imasogie: “Development and Characterization of Isothermally Heat-Treated Nodular Cast Irons,” Ph.D. Thesis, Obafemi Awolowo University, Ile-Ife, Nigeria, 1994.
B.I. Imasogie, J.A. Ali, and A.A. Afonja: “Properties of As-Cast and Heat Treated Nodular Graphite Cast Irons, Melts Treated with CaSi-CaF2 Alloy,” Scand. J. Metall., 2001, 30(2), pp. 91–102.
Y. Tanaka, H. Saito, I. Tokura, and K. Ikawa: “Relationship Between Some Physico-Mechanical Properties and Numerical Indexes of Graphite Shape in Compacted-Vermicular Graphite Cast Irons,” Trans. ASME, 1982, 104, pp. 60–65.
A.G. Fuller, P.J. Emerson, and G.F. Sergeant: “Report on the Effect upon Mechanical Properties of Variations in Graphite Form in Irons Having Various Amounts of Ferrite and Pearlite in the Matrix Structure, and the Use of NDT in Assessments of Mechanical Properties of Such Irons,” AFS Trans., 1980, 88, pp. 21–50.
S.E. Franklin and R.A. Stark: “Application of Secondary Ion Mass Spectroscopy to Study of Graphite Morphology in Cast Iron,” Met. Sci., 1984, 18, pp. 187–200.
J.M. Guilemany and N. Llorca: “Metallographic Differences Between Compacted Graphite Cast Iron and Vermicular Graphite Cast Iron,” Pract. Met., 1984, 21, pp. 299–306.
A.M. Skrebtsov and L. A. Bol’shakov: “Control of the Properties of High-Strength Cast Iron by Inoculants of Different Composition,” Liteinoe Proizvod, 1981, 1, pp. 30–31.
A.M. Petrichenko, V.A. Priymak, and M.V. Mozharov: “Use of Complex Inoculants for Production of Spheroidal Graphite Cast Iron,” Liteinoe Proizvod, 1981, 1, pp. 7–8.
H. Kajoka: “Metal Desulphurization by Calcium-Carbide Injection” in 3rd McMaster Symp. on Iron and Steel Making, External Desulphurization of Hot Metals, McMaster University, Hamilton, ON, Canada, May 1975, pp. 22–23.
K. Kaneko, N. Sano, S. Takenchi, and Y. Matsushita: “Desulphurization and Dephosphurization of Cr-Fe and Si-Cr-Fe Alloys by CaC2-CaF2, CaO-CaF2 and CaSi-CaF2 Fluxes Using Plasma Jet Remelting” in Proc. 3rd Int. Iron and Steel Cong., ISS-AIME, Warrendale, PA, 1978, pp. 583–88.
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Imasogie, B.I. Microstructural features and mechanical properties of compacted graphite iron treated with calcium-magnesium based masteralloy. J. of Materi Eng and Perform 12, 239–243 (2003). https://doi.org/10.1361/105994903770343060
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DOI: https://doi.org/10.1361/105994903770343060