Effect of friction stir processing on fracture toughness and crack growth behaviour of fusion welded 5083 grade aluminum plates

Akçay, Günseli
The purpose was to investigate the effects of post-weld friction stir processing (FSP) on the microstructure and fatigue crack propagation in Aluminum Alloy 5083 H111 weldments. As preliminary study, optimization trials were done in order to decide the type, rotational speed, and travel speed of the FSP tool. Microstructural examinations, hardness and tensile tests were done on as-processed materials. In the second part of the work, FSP was applied on the weld zone of the 5083 H111 plates that were joined by gas metal arc welding and a series of samples were prepared. Tensile, hardness, fracture toughness and fatigue crack propagation tests were carried out on the samples prepared from the base metal, weld metal and FSPed weld metal. Microstructures and fracture surfaces of the samples were investigated by optical microscope and scanning electron microscope. Some improvements in hardness, tensile and fracture properties in the weldment were obtained after FSP, and the results were compared and discussed to explain the reasons and main mechanisms.


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Citation Formats
G. Akçay, “Effect of friction stir processing on fracture toughness and crack growth behaviour of fusion welded 5083 grade aluminum plates,” M.S. - Master of Science, Middle East Technical University, 2015.