A Calculation Model of Carbon Diffusion Coefficient in the Austenite for Spheroidal Graphite Cast Iron

Abstract:

This paper presents the relationship between the carbon atom diffusion coefficient in the austenite and the temperature during the nodular cast iron solidification under different cooling rates or with different carbon contents. Pouring the wedge-shaped casting explores the influence of cooling rate on the diffusion coefficient. The other part explores the change of the diffusion coefficient with different carbon contents by water quenching to save the organization in the solidification. Results show that both the cooling rate and the carbon content can affect the diffusion coefficient, and it decreases as the cooling rate increases. More attempts were also done to correlate the diffusion coefficient with the temperature in different carbon content. It has been found that the diffusion coefficient decreases as the temperature increase.

• Periodical: Materials Science Forum (Volume 789)
• Pages: 593-598
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.789.593
• Online since: April 2014
• Authors: Hong Liang Zheng*, Lin Li, Xin Xin Yuan, Xue Lei Tian
• Keywords: Carbon Content, Cooling Rate, Diffusion Coefficient, Graphite Nodule

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