Journal of Failure Analysis and Prevention

, Volume 13, Issue 1, pp 63–71 | Cite as

Investigation of the Thickness Effect on the Fatigue Strength Calculation

  • A. M. Al-Mukhtar
Technical Article---Peer-Reviewed


The local stress concentrations around the discontinuities and the weld defects are fairly common. In this study, the investigation of thickness and stress concentration effects on fatigue strength (FAT) have been studied. The fracture mechanics tools and fracture analysis code (Franc2D) were used to consider these effects. The FE simulation of welded joints will provide a tool to determine the regions of stress concentration which in turn determine the crack initiating and FAT. Unfortunately, these tools are unable to calculate FAT at higher thicknesses. Therefore, the crack length was corrected with a suitable scale. The determination of fracture toughness values without the need to undertake experiments have been presented.


Crack growth FE simulation Fracture toughness Notches Stress concentration Thickness effect Welding defects Welded joints 



The author would like to thankfully appreciate the support received from the Technische Universität Bergakademie Freiberg, Faculty of Geosciences and Geoengineering, Department for Geology, Germany. The support from the International Institute of Education, USA, is gratefully appreciated. The fruitful discussions with Dr. Z. Barsoum, from the Royal Institute of Technology, Department of Aeronautical and Vehicle Engineering, Stockholm, Sweden are also gratefully acknowledged.


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Copyright information

© ASM International 2012

Authors and Affiliations

  1. 1.Faculty of Geosciences, Geoengineering and MiningTechnische Universität Bergakademie FreibergFreibergGermany

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