Effect of Semi Austempering Treatment on the Fatigue Properties of Ductile Cast Iron

Abstract:

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Single phase bainite structure which is obtained by the conventional austempering treatment reduces the ductility of ductile cast iron. Because of the reduction of ductility it is possible to worsen the fatigue properties. Therefore, semi austempered ductile iron which is treated from  +ϒ is prepared to investigate the static strength and fatigue properties in comparison with fully austempered ductile iron (is treated from ϒ). In spite of semi austempered ductile iron shows the 86% increase of ductility. Also, semi austempered ductile iron shows the higher fatigue limit and lower fatigue crack growth rate as compared with fully austempered ductile iron. By the fractographical analysis, it is revealed that the ferrite obtained by semi austempering process brings about the plastic deformation(ductile striation) of crack tip and gives the prior path of crack propagation. The relatively low crack growth rate in semi austempered specimen is caused by above fractographical reasons

Info:

Periodical:

Key Engineering Materials (Volumes 345-346)

Edited by:

S.W. Nam, Y.W. Chang, S.B. Lee and N.J. Kim

Pages:

295-298

DOI:

10.4028/www.scientific.net/KEM.345-346.295

Citation:

B. Lim and Y. W. Choi, "Effect of Semi Austempering Treatment on the Fatigue Properties of Ductile Cast Iron", Key Engineering Materials, Vols. 345-346, pp. 295-298, 2007

Online since:

August 2007

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$35.00

[1] Rao, P. Prasad and Putatunda, Susil K., Investigations on the Fracture Toughness of Austempered Ductile Irons Austenitized at Different Temperatures, Materials Science and Engineering A, Vol. 349 No. 1(2003), pp.136-149.

DOI: 10.1016/s0921-5093(02)00633-0

[2] Kim, M. G. and Kim, J. H., Influence of Matrix Structural and Mechanical Factors on Fatigue Limit in Austempered Ductile Iron, Trans. of KSME (A), Vol. 23, No. 2(1999), p.287~293.

[3] Dommarco, R. C., Bastias, P. C., Dall'O, H. A., Hahn, G. T., and Rubin, C. A., 1998, Rolling Contact Fatigue RCF Resistance of Austempered Ductile Iron(ADI), Wear, Vol. 221 No. 1, p.69~74.

DOI: 10.1016/s0043-1648(98)00259-2

[4] Lin, C. K. Lai, P. K. and Shih, T. S., Influence of Microstructure on the Fatigue Properties of Sustempered Ductile Irons-I. High-Cycle Fatigue, International Journal of Fatigue, Vol. 18, No. 5(1996), p.297~307. �.

DOI: 10.1016/0142-1123(96)82895-7

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