Phase Transformations and XRD Analysis of Austempered Ductile Iron

Abstract:

This research penetrated on the transformation of phases in the microstructures of austempered ductile iron with respect to different austempering holding times. Ductile iron samples were constituted in form of Y block double cylinder with dimension of 300m x Ø25mm through CO2 sand casting process in 60 kg capacity furnace. Austempering process were conducted by first austenitizing the samples at temperature of 900°C for 1 hour. The process continues by rapidly quenched the samples inside salt bath furnace at 350°C for three different holding times of 1 hour, 2 hours and 3 hour. Samples were then taken out and cooled at room temperature. Samples were then prepared in accordance to standard metallographic process and observed using Tabletop Scanning Electron Microscopy (SEM) model Hitachi TM3000. Phases were then verified through X-Ray Diffraction analysis (XRD) test by Rigaku diffractometer. The phase structures of as cast ductile iron mainly consisted of graphite nodules embedded in ferrite and pearlite phases Austempering the samples for 1 hour holding time promoted the structures of ferrite platelets and bainitic structures surrounding the graphite. Longer austempering holding times resulted in coarsening of the ferrite platelets structures and transformation from lower bainite to upper bainite structures.

• Periodical: Advanced Materials Research (Volume 402)
• Pages: 187-190
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.402.187
• Online since: November 2011
• Authors: Bulan Abdullah, S. K. Alias, A. Jaffar, M. F. Idham, A. Ramli
• Keywords: Austempered Ductile Iron, Phases, X-Ray Diffraction (XRD)

References

[1] William F. Smith, Structure and Properties of Engineering Alloys, 2nd Edition. McGraw-Hil, Inc. (1993).

[2] Serope Kapakjian, Manufacturing Engineering and Technology. 6th edition in SI unit. Prentice Hall International, (2010).

[3] Simon Day (2008), information on http://www.aditreatments.com

[4] J. Zimba, D.J. Simbi and E. Navara Cem. & Con Com vol 25 (2003), p.643–649.

[5] A.H. Elsayed et.al, Mtrl and Dsgn vol 30 (2009) p.1866–1877

[6] B. Abdullah, A. Jaffar, S.K. Alias, R. Jaafar, A. Ramli and A.Faitullah. Proceedings of SPIE: The International Society for Optical Engineering 7522 (2010) art. No. 7522450

[7] G.Francucci, J. Sikora and R. C.Dommarco. Mater. Sci. and Eng: A, vol 485 ( 2008) pp.46-54

[8] L.C. Chang, I.C. Hsui , L.H. Chen and T.S. Lui. Wear vol. 260 (2006), p.783–793

[9] O. Eric, L. Sidjanin, Z. Miskovic, S. Zec. Mater Lttrs vol.58 (2004) p.2707– 2711

[10] J.M. Radzikowska. Mater Charac. Vol 54 (2005) pp.287-304.

[11] K.L. Hayrynen. 2002 World Conference on ADI (2002et.al, Mtrl and Dsgn vol 30 (2009) p.1866–1877.