The Influence of Austempering Heat Treatment Variables on Dimensional Changes of a Ni-Cu Ductile Iron

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Control and prediction of the dimensional changes (DC) during austempering heat treatment of ductile iron is difficult because many factors influence this behavior. In the present work cylindrical specimens of ductile iron were used to study the effect of austenitizing temperature, austempering time, temperature, and prior microstructure on DC. The results show that DC increases with increasing austenitizing temperature in the range of 850 to 950°C with a fully ausferrite microstructure. Evaluation of different combinations of ferrite and pearlite contents in prior microstructure indicates that a fully ferritic structure has the highest DC. In addition, results show that by lowering austempering temperature from 400 to 250°C, DC increases.

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Periodical:

Materials Science Forum (Volumes 514-516)

Edited by:

Paula Maria Vilarinho

Pages:

702-706

DOI:

10.4028/www.scientific.net/MSF.514-516.702

Citation:

S. Yazdani "The Influence of Austempering Heat Treatment Variables on Dimensional Changes of a Ni-Cu Ductile Iron", Materials Science Forum, Vols. 514-516, pp. 702-706, 2006

Online since:

May 2006

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$35.00

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DOI: 10.1016/0025-5416(87)90556-8

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