Literature review on crack retrofitting in steel by Tungsten Inert Gas remelting

Welded metallic structures are usually prone to different forms of degradation in the mechanical properties during their life span such as fatigue. Tungsten Inert Gas remelting is a post-weld treatment method that gained increasing interest in the last decades. However, more light should be thrown on the behaviour of the existing cracked structures retrofitted by TIG-remelting. Therefore, fatigue test results of several welded details improved TIG-remelting have been extracted. Around 130 test results with different existing crack sizes are presented and analyzed. The gain factor in fatigue is defined and calculated for the collected data. TIG-remelting shows high potential in life extension. In fact, TIG-remelting is found to give a fair life extension greater than the design life of the new details even when 2 crack mm remains. Besides, toe radius and residual stresses are found to vary significantly after TIG-remelting depending on the remelting parameters and the steel type