Fatigue crack repair in welded structures via tungsten inert gas remelting and high frequency mechanical impact
Journal article, 2020

Rehabilitation of welded structures has gained increasing attention lately. This paper aims at investigating the efficiency of Tungsten Inert Gas (TIG)-remelting and TIG-remelting followed by High Frequency Mechanical Impact treatment (TIG-HFMI) in fatigue life extension. Fatigue tests were carried out on as-welded and cracked specimens after treatment. The lives of the treated specimens increased remarkably by the two methods (TIG and TIG-HFMI). Many of the treated specimens ran-out after 10 million cycles of loading and failed at the clamping location when tested at a higher stress range. The improvement in compressive residual stresses, hardness values and weld toe radii were the reasons behind the life extension. These factors were used for fatigue life estimation in as-welded and TIG-treated specimens using the base metal S[sbnd]N curve. Moreover, the test results together with results from previous tests in the literature demonstrated that these methods can be useful for crack retrofitting as for new structures.

High frequency mechanical impact

Life extension

Crack retrofitting

Crack repair

TIG remelting



Hassan al-Karawi

Chalmers, Architecture and Civil Engineering, Structural Engineering

R. U.Franz von Bock und Polach

Technical University of Hamburg (TUHH)

Mohammad al-Emrani

Chalmers, Architecture and Civil Engineering, Structural Engineering

Journal of Constructional Steel Research

0143-974X (ISSN)

Vol. 172 106200

Subject Categories

Applied Mechanics

Manufacturing, Surface and Joining Technology

Other Materials Engineering



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