Fatigue Curves for Aluminium Alloys and their Welded Joints Used in Automotive Industry

Our research work has focused from the materials world on the aluminium alloys, from the manufacturing processes on the welding technologies, and from different loads on the cyclic loads. The article aimed (i) to demonstrate the behaviour of the friction stir welded (FSW) joints under cyclic loading conditions; (ii) to determine fatigue (limit) curves for two aluminium alloys and their welded joints. Experiments were performed on 5754-H22 and 6082-T6 aluminium alloys and their FSW joints. Both high cycle fatigue (HCF) and fatigue crack propagation (FCG) tests were executed on both base materials and their welded joints. Statistical behaviour of the base materials and welded joints was represented by the cutting of the specimens and the using of different crack paths. HCF limit curves were determined based on staircase method and FCG limit curves can be determined by own developed six step method. The investigations and their results were compared with each other and with the results can be found in the literature.