The Relationship between Fatigue Crack Growth and Residual Stress in Rails

Residual stress and fatigue crack growth rates are important to determine mechanical behavior of rails. This study aims to make relationship between residual stress and fatigue crack growth values in rails. For this purpose, three R260 quality rails (0.6-0.8% C, 0.6-1.25 Mn) were chosen. Residual stress of samples was measured by cutting method that is related in railway standard. Then samples were machined for fatigue crack growth test and analyze was completed according to the ASTM E647 standard which gives information about parameters of rails for this test. Microstructure characterizations were examined by Light Optic Microscope (LOM). The results showed that residual stress change with fatigue crack growth rate. The sample has highest residual stress exhibits highest crack growth rate and pearlitic structure can be seen clearly for all samples by microstructure analyze.

• F. Husem
• M. E. Turan
• Y. Sun
• H. Ahlatci
• I. Tozlu

• Residual stress
• fatigue crack growth
• R260
• LOM
• ASTM E647.

[1] ASTM E647-13: Standard test method for measurement of fatigue crack growth rates, 2015.
[2] ASTM E399-12Ɛ3: Standard test method for linear elastic plane strain fracture toughness KIC for metallic materials, 2013.
[3] ASTM E1820-13: Standard test method for fracture toughness, 2014
[4] TS EN 13674-1: Railway Applications – Track – Rail – Part 1: Vignole Railway Rails 46 kg/m and Above, Brussels, 2011
[5] Yiğit, O., Dilmeç, M., ve Halkacı, S., “Tabaka kaldırma yöntemiyle kalıntı gerilmelerin ölçülmesi ve diğer yöntemlerle karşılaştırılması” Mühendis ve Makine Dergisi, 49 (579): 12-16, 2008
[6] Ortadoğu Rulman Sanayi ve Ticaret A. Ş, “Ors rulmanları ve Makaralarının yorulma ömrünün artırılması için kalıcı gerilmelerin iyileştirilmesi”, ORS Bülteni, Sayı 5, 2004.
[7] Totten, G., Howes, M., and Inoue, T., “Handbook of Residual Stress and Deformation of Steel”, Materials Park, Ohio, 424-436, 2002.
[8] D.A Lados, D. Apelian, “The Effect of Residual Stress on the Fatigue Crack Growth Behavior of Al-Si-Mg Cast Alloys -Mechanisms and Corrective Mathematical Models”, Mechanical Engineering Faculty Publications, 2006
[9] J. Toribio, J.C Matos, B. González, J. Escuadra, “Fatigue crack growth in round bars for rock anchorages: the role of residual stresses”, Procedia Structural Integrity vol.2, pp.2734, 2016
[10] J.Z. Zhou, S. Huang, L.D. Zuo, X.K. Meng, J. Sheng, Q. Tian, Y.H. Han, W.L. Zhu, “Effects of laser peening on residual stresses and fatigue crack growth properties of Ti–6Al–4V titanium alloy”, Optics and Lasers in Engineering vol.52, pp.189, 2014
[11] J.W. Sowards, T. Gnäupel-Herold, J.D. McColskey, V.F. Periara, A.J. Ramirez, “Characterization of mechanical properties, fatigue-crack propagation, and residual stresses in a microalloyed pipeline-steel friction-stir weld”, Materials & Design vol.88, pp.632, 2015