The effect of copper on the microstructure and aging characteristics of an 0.8%C bainitic steel

Yıldırım, Çağatay
Copper causes hot shortness in steel. However, the 1:2 nickel-to-copper ratio avoids hot shortness phenomena. Also, it is known that an aging treatment applied to ferritic steels causes age hardening via the precipitation of Cu in the form of BCC copper-rich clusters. The latter phenomenon was studied extensively in low and medium-carbon steels. In this study, the copper precipitation in bainitic high-carbon steel and its effect on microstructure and properties are investigated. To achieve this, 0.8% C steel having 2% copper and 1% nickel was cast and isothermally heat treated at various temperatures to obtain bainite. Then the bainitic steels were aged at various temperatures and times. Copper could not suppress carbide precipitation and as a result, retained austenite phase could not be detected in bainitic structures. However, aging retards further softening of the bainite structure in comparison to martensitic specimens.


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Citation Formats
Ç. Yıldırım, “The effect of copper on the microstructure and aging characteristics of an 0.8%C bainitic steel,” M.S. - Master of Science, Middle East Technical University, 2022.