Conventional ductile iron (DI) and austempered ductile iron (ADI) alloys
were successfully produced. The alloying elements—Ni, Mo, Cr and Mn were added
to get as-cast low-alloyed ductile iron (LADI) followed by austempering heat
treatment. Hardness was measured for all investigated alloys. A hardness conversion
table was deduced for irons investigated. Highest values of calculated quality
index (QI) were for ADI alloys implying higher material performance. Impact
energy values were attributed to microstructure and tensile properties. Wear
characteristics of selected ADI alloys showed comparable values with LADI. Micro-hardness
values were used to identify the micro-constituents and the work-hardened
layers. Fracture modes were revealed and fracture surface observations were
done by SEM. Due to higher toughness and QI, and cheap price, it is suggested
that rolling mills may be produced from ADI, specially heat-treated instead of
Cite this paper
Fatahalla, N. and Hussein, O. (2015). Microstructure, Mechanical Properties, Toughness, Wear Characteristics and Fracture Phenomena of Austenitised and Austempered Low-Alloyed Ductile Iron. Open Access Library Journal, 2, e1012. doi: http://dx.doi.org/10.4236/oalib.1101012.
Stokes, B., Gao, N. and Reed, P.A.S. (2007) Effects of Graphite Nodules on Crack Growth
Behaviour of Austempered Ductile Iron. Materials Science and
Engineering A, 445-446, 373-385. http://dx.doi.org/10.1016/j.msea.2006.09.058
Fatahalla, N., AbuElEzz, A. and Semeida, M. (2009) C, Si and Ni as Alloying
Elements to Vary Carbon Equivalent of Austenitic Ductile Cast Iron:
Microstructure and Mechanical Properties. Materials Science and Engineering
A, 504, 81-89. http://dx.doi.org/10.1016/j.msea.2008.10.019
Fatahalla, N., Bahi, S. and Hussein, O. (1996) Metallurgical
Parameters, Mechanical Properties and Machinability of Ductile Cast Iron. Journal of Materials Science, 31, 5765-5772. http://dx.doi.org/10.1007/BF01160826
M. (1993) An Update on Austempered Ductile Cast Iron. Proceedings of the International Conference
on Mechanical Behaviour of Ductile Cast Iron and Other Cast Metals,
Kitakyushu, 30 July-1 August 1993, 319-326.
K.M., Nofal, A.A. and Ibrahim, M.M.
(2008) Effect of Alloying Additions and Two-Step
Austmpering on the Microstructure and Mechanical Properties of Ductile Iron. Proceedings
of the 9th International Conference on Mechanical Design and
Production (MDP-9), Cairo, 8-10 January 2008.
Bartosiewicz, L., Singh, I., Alberts,
F.A., Krause, A.R. and Putatunda, S.K.
(1995) The Influence of Chromium on Mechanical Properties of Austempered
Ductile Cast Iron. Journal of Materials Engineering and Performance, 4, 90- 101. http://dx.doi.org/10.1007/BF02682710
Putatunda, S.K., Kesani, S., Tackett, R. and Lawes, G. (2006) Development of Austenite Free
ADI (Austempered Ductile Cast Iron). Materials Science
and Engineering: A, 435-436, 112. http://dx.doi.org/10.1016/j.msea.2006.07.051
S. and Priestner, R.
(1995) High Temperature Decomposition of Austempered
Microstructures in Spheroidal Graphite Cast Iron. Materials Science and Technology, 11, 901-907. http://dx.doi.org/10.1179/mst.19126.96.36.1991
K.M.I. (2000) Effect of Molybdenum and Nickel Additions on Microstructure and
Mechanical Properties of As-Cast and Austempered Ductile Cast Iron. Doctoral
Dissertation, Technical University of Berlin, Berlin.
Velez, J.M., Garboggini, A. and Tschiptschin, A.P.
(1996) Effect of Silicon on Kinetics of Bainitic Reaction in Austempered
Ductile Cast Iron. Materials Science and Technology, 12, 329-337. http://dx.doi.org/10.1179/mst.19188.8.131.529
Volkov, K.G., et al. (1993) Silicon and Heat Treatment Parameters Effects on Austempering
Ductile Iron Structure and Mechanical Properties. Proceedings
of the 34th Mechanical Working and Steel Processing Conference,Montreal, 25- 28 October
Aranzabal, J., Gutierrez, I., Rodriguez-Ibabe, J.M. and Urcola, J.J. (1997) Influence of the Amount and Morphology
of Retained Austenite on the Mechanical Properties of an Austempered Ductile
Iron. Metallurgical and Materials Transactions A, 28, 1143-1156. http://dx.doi.org/10.1007/s11661-997-0280-6
Kobayashi, T. and Yamamoto, S.
(1996) Effect of
Holding Time in the (αγ)
Temperature Range on Toughness of Specially Austempered Ductile Iron. Metallurgical and Materials Transactions A, 27, 1961-1971.
K.S., Rao, P.P. and Udupa, K.R.
(2010) Improvement in Fracture Toughness of
Austempered Ductile Iron by Two-Step Austempering Process. International Journal of Cast Metals
Research, 23, 330-343.
Udupa, K.R. and Rao, P.P.
(2008) Development of Austempered
Ductile Iron for High Tensile and Fracture Toughness by Two Step Austempering
Process. Proceedings of the 68thWorld Foundry Congress, Chennai, 7-10 February 2008, 35-40.