MSA  Vol.4 No.2 , February 2013
Effect of Notch Severity on Fatigue Behaviour of ADI Castings
ABSTRACT

An investigation was carried out to examine the influence of notch sensitivity on fatigue behaviour of austempered ductile iron (ADI). Samples were made of ductile iron with a chemical composition of 3.55% C, 2.18% Si, 0.35% Mn, 0.022 P, 0.008 S and 0.045% Mg. The samples were heat treated by austenitizing at 900 for 1 h and then rapidly quenched into two different salt baths at 350 and 400 for 1 h each. This work aims at studying the capability of mechanical stress analysis software (ANSYS 12.0), as a nondestructive tool, to characterize and quantify the fatigue strength of the notched ADI samples with different radii (from 1 to 3 mm). In addition, experimental testing was performed using rotary bending fatigue machine on notched samples with radii of 1, 1.5 and 2-mm to verify the theoretical data obtained by ANSYS-12. The results show that the predicted fatigue strength estimated by ANSYS-12 is very close to the experimental one. Therefore, fatigue performance of the rotating parts made of ADI can be estimated theoreticcally using ANSYS 12.0. The fatigue strength of these parts can also be improved by increasing the formed filled radius due to decreasing the notch sensitivity factor.


Cite this paper
K. Ibrahim, B. El-Sarnagawy and I. Saleh, "Effect of Notch Severity on Fatigue Behaviour of ADI Castings," Materials Sciences and Applications, Vol. 4 No. 2, 2013, pp. 109-117. doi: 10.4236/msa.2013.42012.
References
[1]   B. Atzori, M. Zappalorto and F. Berto, “A Theoretical Treatise for Notch and Defect Sensitivity under Torsion,” Mechanism Research Communications, Vol. 37, No. 2, 2010, pp. 173-176.

[2]   C. Brunetti, M. V. Leite and G. Pintaude, “Effect of Specimen Preparation on Contact Fatigue Wear Resistance of Austempered Ductile Cast Iron,” Wear, Vol. 263, No. 1-6, 2007, pp. 663-668.

[3]   A. N. Damir, A. Elkhatib and G. Nassef, “Prediction of Fatigue Life Using Modal Analysis for Grey and Ductile Cast Iron,” International Journal of Fatigue, Vol. 29, No. 3, 2007, pp. 499-507. doi:10.1016/j.ijfatigue.2006.05.004

[4]   R. C. Dommarco and J. D. Salvanda, “Contact Fatigue Resistance of Austempered and Partially Chilled Irons,” Wear, Vol. 254, No. 3-4, 2003, pp. 230-236.

[5]   O. Eric, D. Rajnovic, S. Zec, L. Sidjanin and M. T. Jova novic, “Microstructure and Fracture of Alloyed Austempered Ductile Iron,” Materials Characterization, Vol. 57, No. 4-5, 2006, pp. 211-217.

[6]   Y.-J. Kim, H. Shin, H. Park and J. D. Lim, “Investigation into Mechanical Properties of Austempered Ductile Iron (ADI) in Accordance with Austempering Temperature,” Materials Letters, Vol. 62, No. 3, 2008, pp. 357-360.

[7]   C. K. Lin, P. K. Lai and T. S. Shih, “Influence of Microstructure on the Fatigue Properties of Austempered Ductile Iron-I. High Cycle Fatigue,” International Fatigue Journal, Vol. 18, No. 5, 1996, pp. 297-307. doi:10.1016/0142-1123(96)82895-7

[8]   S. K. Putatunda, S. Kesani, R. Tackett and G. Lawes, “Development of Austenite Free ADI-Austempered Ductile Cast Iron,” Materials Science and Engineering A, Vol. 435-436, 2006, pp. 112-122.

[9]   P. P. Rao and S. K. Putatunda, “Investigation on The fracture Toughness of Austempered Ductile Iron Alloyed with Chromium,” Materials Science and Engineering A, Vol. 346, No. 1-2, 2003, pp. 254-265.

[10]   P. A. S. Reed, R. C. Thomsin, J. S. James, D. C. Putman, K. K. Lee and S. R. Gunn, “Modelling Microstructural Effects in the Fatigue of Austempered Ductile Iron,” Materials Science and Engineering A, Vol. 346, No. 1-2, 2002, pp. 273-286. doi:10.1016/S0921-5093(02)00545-2

[11]   J. Speer, D. K. Matlock, B. C. De Cooman and J. G. Schroth, “Carbon Partitioning into Austenite after martensite Transformation,” Acta Materialia, Vol. 51, No. 9, 2003, pp. 2611-2622.

[12]   B. Stokes, N. Gao and P. A. S. Reed, “Effect of Graphite Nodules on Crack Growth Behaviours of Austempered Ductile Iron,” Materials Science and Engineering A, Vol. 445-446, 2007, pp. 374-385.

[13]   A. H. Elsayed, M. M. Megahed, A. A. Sadek and K. M. Abouelela, “Fracture Toughness Characterization of Aus tempered Ductile Iron Produced Using Both Conventional and Two-Step Austempering Processes,” Materials & Design, Vol. 30, No. 6, 2009, pp. 1866-1877.

[14]   N. Elmasry, A. kandil, K. Abouelela and A. Amer, “Wear Behaviour of Austempered Ductile Cast Iron,” Met all-Fourschung, Vol. 64, No. 1-2, 2010, pp. 353-357.

[15]   M. Tayanc, K. Aztekin and A. Bayram, “The Effect of Matrix Structure on the Fatigue Behaviour of Austempered Ductile Iron,” Materials and Design, Vol. 28, No. 3, 2007, pp. 797-803.

[16]   J. Yang and S. K. Putatunda, “Near Threshold Fatigue Crack Growth Behaviour of Austempered Ductile Cast Iron (ADI) Processed by a Novel Two-Step Austempering Process,” Materials Science and Engineering A, Vol. 393, No. 1-2, 2005, pp. 254-268.

[17]   J. Zimba, D. J. Simbi and E. Navara, “Austempered Ductile Iron: An Alternative Material for Earth Moving Components,” Cement & Concrete Composites, Vol. 25, No. 6, 2003, pp. 643-649.

 
 
Top