FATIGUE DAMAGE OF 2024-T351 ALUMINIUM ALLOY FRICTION STIR WELDING JOINTS. PART 1: CHARACTERISATION

Aidy  Ali; Mike  W. Brown; Omar  Suliman Zaroog

Authors

Aidy Ali Fatigue and Fracture Research Group, Department of Mechanical and Manufacturing Engineering, University of Putra Malaysia
Mike W. Brown Department of Mechanical Engineering, The University of Sheffield, Mappin Street, Sheffield, S1 1JD, United Kingdom
Omar Suliman Zaroog Fatigue and Fracture Research Group, Department of Mechanical and Manufacturing Engineering, University of Putra Malaysia, 43400 Serdang, Selangor, Malaysia

Keywords:

2024-T351 Aluminium alloy, fatigue, friction stir welding (FSW)

Abstract

Characterisation of macrostructure, microstructure, hardness, residual stress and cyclic deformationbehaviour of 2024-T351 Aluminium Alloy FSW joints has been conducted in order to characterise thecritical areas for fatigue crack initiation. Inhomogeneous micro-parameters that govern the nonuniformresidual stresses and cyclic strength are then discussed. The cyclic strength of the weldmicro-regimes are controlled by grain size and distribution of precipitates achieved during the weldprocess. The comprehensive information of micro and macro mechanics gathered is used to assist inunderstanding the mechanism that governed the fatigue crack initiation, propagation, and life of thisweld.

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