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Cracks on metallic components may appear due to manufacturing, handling, installation, repair, welding etc. and are controlled by quality documents. However, if cracks violate the limit defined in quality document, then either parts will be scraped or will need additional evaluation through detailed fracture mechanic’s approach. The initial size and shape of a crack, part geometry and loading, highly impacts the behavior of a crack’s growth and remaining useful life. Industry standard software like ANSYS, AFGROW, Franc3D, etc. offer the solution to estimate the stress intensity factor and crack growth rate. However, these software’s have their limitation and start showing the deviation for complex geometry and loading scenario.

The effect of notches & mean stress in fatigue of materials has been a subject of wider interest. The current study is focused on alpha-beta Titanium alloy (Ti-6Al-4V) which is a common material in aerospace applications. Various mean stress correction approaches are evaluated for notched & un-notched specimens. Life predictions are obtained for a standard test specimen. For the zero mean condition, most approaches predict similar life. However for non-zero mean conditions, significant deviation is observed in life predictions for Titanium alloy (Ti-6Al-4V). Walker mean stress correction approach was found to be in close agreement with published test data. Walker constant is a significant parameter which influences life prediction accuracy. Study has been carried out to find suitable values of constant for different standard shapes/forms of raw material used for manufacturing.