Influence of Magnetic Field on the Mechanical Properties of Austempered Ductile Iron (ADI)


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A novel concept of two-step austempering in a magnetic field has been conceived by this investigator. This twostep process involves first quenching the alloy to a lower temperature after austenitizing and then immediately rising the temperature of the quenching media to a higher temperature and the whole austempering process is carried out in the presence of a high magnetic field. In this investigation, Austempered Ductile Iron (ADI) was processed by this novel two-step austempering process in a high magnetic field of 20 Tesla. The microstructure and the mechanical properties of the ADI processed in a magnetic field has been characterized and compared with ADI processed by conventional process. The results of this investigation indicate significant improvement in the mechanical properties of ADI when Austempered in a high magnetic field. Both yield and tensile strengths were higher in the samples processed in the presence of a magnetic field. Very fine grain ferrite and austenite was obtained in the microstructure. The ferrite content was also significantly higher.



Materials Science Forum (Volumes 539-543)

Main Theme:

Edited by:

T. Chandra, K. Tsuzaki, M. Militzer , C. Ravindran




S. K. Putatunda, "Influence of Magnetic Field on the Mechanical Properties of Austempered Ductile Iron (ADI)", Materials Science Forum, Vols. 539-543, pp. 4657-4662, 2007

Online since:

March 2007




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