Research Article

Quantitative Evaluation of Carbon-Enriched Stabilised Austenite in Cast Austempered Ductile Iron of Varying Section Thickness

Olawale John Oluyemi1*, Ibitoye Simeon Ademola1, Oluwasegun Kunle Michael.1
1 Department of Materials Science and Engineering, Obafemi Awolowo University, Ile-Ife. Nigeria
* Corresponding author: olawalejohnoluyemi@njmse.msn.ng
Published: Jun, 2018
Pages: 1-9

Abstract

The quantity of carbon-enriched stabilised austenite (γHC) in austempered ductile iron (ADI) with various casting  thicknesses was evaluated in this study. Ductile iron grade that conforms to ASTM A536 65-45-12 was cast,  specimens of section thickness in the range of 5 to 25 mm were machined, isothermally treated to 820°C austenitising  temperature, and austempered at austempering temperature (T ) of 300 and 375°C. The resulting phase distributions  A  of treated specimens were characterised using X-Ray Diffraction (XRD) method. The patterns of XRD were found to  consist of ferrite (α) and austenite (γ) phases. The percentage volume of carbon-enriched stabilised austenite in the  ADI decreased as section thickness increased. It was concluded that the carbon-enriched stabilised austenite in ADI  depends on the casting section thickness and austempering temperature

Keywords

Ductile iron; Aaustempered ductile iron; Carbon stabilised austenite; Acicular ferrite; Casting thickness

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How to Cite

Oluyemi, O. J., Ademola, I. S., & Michael., O. K. (2018). Quantitative Evaluation of Carbon-Enriched Stabilised Austenite in Cast Austempered Ductile Iron of Varying Section Thickness. Nigerian Journal of Materials Science and Engineering, 8(1), 1-9.

O. J. Oluyemi, I. S. Ademola, and O. K. Michael., "Quantitative Evaluation of Carbon-Enriched Stabilised Austenite in Cast Austempered Ductile Iron of Varying Section Thickness," Nigerian Journal of Materials Science and Engineering, vol. 8, no. 1, pp. 1-9, June 2018.

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