In this thesis, friction stir channeling (FSC) and its process parameters influence on geometry, surface quality and productivity are explored. The probe of the friction stir processing (FSP) tool used to perform these tests was a modified submerged bobbin tool made of MP 159 Co-Ni alloy. The body was made from H13 tool steel. To find the optimal channel conditions for a targeted range of process parameters, multiple 6061 aluminum samples were prepared with a U shape guide to test the effects of different spindle speeds and feed rates. Using a gantry-type computer numerical control (CNC) friction stir welding (FSW) machine, the aluminum coupons were subjected to calibration experiments, force control tests, and an increased production rate to test these effects. It was found through experimentation that the programmed feed rates, spindle speeds and forces produced by the machine had an impact on the channel geometry. It was determined from the force-controlled setup that 8.46 mm/s at 750 RPM was the best combination of results for the four conditions tested on a CNC friction stir processing-machine. It was then tested at 10.58 mm/s at 800 RPM, which had comparable results with the best combination of input parameters from the force-controlled runs which demonstrates the utility of the process in high production settings. Finally, a proof-of-concept experiment was performed on a robotic arm outfitted with a FSW holder, showing acceptable results. This is a validation of its future implementation in the manufacturing of large parts for lightweight, aerospace, and automotive applications.

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Dans le domaine des matériaux métalliques, les techniques d’assemblage par soudageconduisent à des réductions de masse et de coûts importantes susceptibles d’intéresserles industries aéronautiques. Néanmoins, les procédés de soudage classiquespar fusion ne s’appliquent pas aux dernières générations d’alliages d’aluminium aéronautiques.Dans ce contexte, le procédé de soudage Friction Stir Welding présentedes atouts considérables, de nature à rendre compétitives les structures métalliquesface à la montée en puissance des matériaux composites.L’objectif de cette thèse est double. Il s’agit d’une part d’améliorer notre compréhensiondu procédé de soudage Friction Stir Welding Bobbin Tool puis dans undeuxième temps de proposer une méthodologie visant à prédire les paramètres desoudage optimaux.Afin de mener à bien ces objectifs, des essais de soudage ont été menés pour troisalliages d’aluminium aéronautique, incluant deux alliages d’aluminium-lihtium, etdeux épaisseurs, représentatives d’une jonction de peau de fuselage. Les résultatsd’essais ont par la suite été exploités et ont permis de mettre en évidence des corrélationsentre paramètres de soudage, température, puissance et malaxage du noyausoudé.Dans un troisième temps, afin de supporter la démarche expérimentale, des outilsde simulation ont été utilisés. Un modèle thermo-fluide local a été développé afinde simuler les phénomènes de malaxage dans le noyau soudé. A l’échelle globale, unmodèle thermique a permis de reproduire fidèlement les phénomènes de diffusion dela chaleur dans la structure. Enfin, le couplage des deux modèles a montré qu’il étaitpossible de simuler puis de prédire un domaine de soudabilité. / In the field of metallic materials, welding technologies can provide significantmass reductions and cost savings to aircraft industries. Nevertheless, classical fusionwelding processes can not be applied to last generations of aeronautical aluminiumalloys. In this context, Friction Stir Welding offers many advantages and can helpmetallic parts to face the build up of composite materials.This thesis has mainly two objectives. We aim first at improving our understandingof Friction Stir Welding with Bobbin Tool and then at proposing a kind ofmethodology able to predict optimal welding parameters.Welding trials were carried out using three aeronautical aluminium alloys includingtwo aluminium lithium and two thicknesses representative of a fuselagejunction. Results were analyzed and some correlations were found between weldingparameters, temperature and stirring of the weld nugget.This work was also supported by several modeling tools. A local thermo-fluidapproach has been used to simulate stirring of the material in the weld nugget. Aglobal thermal model has been used to simulate heat diffusion in the structure. Then,a coupled approach of these previous modeling tools shows that it was possible tonumerically predict a processing window.

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