The Effect of Butt-weld Defects of Aluminum Joints on Fatigue Life Using Basquin Prediction Model

  IJETT-book-cover  International Journal of Engineering Trends and Technology (IJETT)          
© 2018 by IJETT Journal
Volume-65 Number-2
Year of Publication : 2018
Authors : Mohammed Algarni, Mohammed Zwawi
DOI :  10.14445/22315381/IJETT-V65P217


MLA Style: Mohammed Algarni, Mohammed Zwawi "The Effect of Butt-weld Defects of Aluminum Joints on Fatigue Life Using Basquin Prediction Model" International Journal of Engineering Trends and Technology 65.2 (2018): 92-95.

APA Style:Mohammed Algarni, Mohammed Zwawi (2018). The Effect of Butt-weld Defects of Aluminum Joints on Fatigue Life Using Basquin Prediction Model. International Journal of Engineering Trends and Technology, 65(2), 92-95.

Discontinuities and voids in weldments affect the fatigue life of welded joints. An example of these discontinuities in a welded joint is undercut. The undercut causes high-stress concentrations on the joints that are calculated based on the root radius and depth of the undercut. Therefore, different undercuts cause varying stress concentration increases based on their geometry. Numerous undercut geometries can be found with different levels of effects on fatigue life. Industrial codes and operational standards set conservative tolerances for undercut geometries. Thus, the need for one model that is capable of predicting the fatigue limit for various undercuts is crucial. From this point of view, this paper investigates the capability of the phenomenological Basquin fatigue model for predicting the fatigue life of different undercut geometries. The research is based on a scripted code in VBA using the least square method for calibration and compares the code results to experimental fatigue data. The research results show the good agreement of the Basquin model prediction compared to experimental results.

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Fatigue life, Undercut, butt-weld, Basquin model, Notch