Microstructure of thin-wall ductile iron castings

Conference · Mon Oct 01 04:00:00 EDT 2001

OSTI ID:900352

Dogan, Omer N; Schrems, Karol K; Hawk, Jeffrey A; Druschitz, A P ^[1]

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1. Intermet Corp., Lynchburg, VA

The automotive industry is seeking to replace current car parts made of aluminum and iron castings with thin wall (down to 2 mm) iron castings to reduce the cost and weight of automobiles. The mechanical properties of thin wall ductile iron castings are affected strongly by the thickness of the castings. The thinner castings cool at a faster rate, and microstructural features that form during solidification, and subsequently, transform in the solid state, are strongly dependent on a geometrical parameter related to the ratio of surface area-to-volume of the casting. As this ratio becomes larger, castings cool faster. As a result, the nodule count on the observation plane of the specimens increases dramatically (>2000 nodules/mm2 in most specimens), i.e. as the thickness of castings decreases. Also, the matrix of the thin walled ductile iron castings becomes more ferritic as the ratio of surface area-to-volume decreases.

• Research Organization: Albany Research Center (ARC), Albany, OR
• Sponsoring Organization: USDOE - Office of Fossil Energy (FE); American Foundry Society, Des Plaines, IL
• OSTI ID: 900352
• Report Number(s): DOE/ARC-2001-009; CRADA 0976
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM
AUTOMOBILES
AUTOMOTIVE INDUSTRY
CASTING
CASTINGS
IRON
MECHANICAL PROPERTIES
MICROSTRUCTURE
SOLIDIFICATION
THICKNESS
automotive industry
casting thickness
cooling rate
mechanical properties
microstructure
thin-wall ductile iron castings