Friction stir forming is a joining process that can be employed for different types of mechanical connections. The idea is to deform one material and mechanically interlock with a second material exploiting an enhanced ductility at elevated temperature resulting from stir heating. A rigid rotating tool is plunged and, subsequently, moved in a parallel direction to the plane of the upper sheet pushing the material into holes or grooves of the part, placed below, to be joined. Herein, experimental tests were executed by changing the main process variables with the aim of highlighting their effects on the material flow during the studs' extrusion. An aluminum alloy of the same chemical composition, but with two different heat treatments, was processed pointing out the influence of the alloy's mechanical properties on the process dynamics and final stud integrity. An evolution of the microstructure as a result of the process thermo-mechanical conditions is also provided. Furthermore, a full design of experiments was executed to highlight the influences of analyzed input parameters on the stud dimensions. The cross-section area of each extruded stud was measured and analyzed for the joint interlocking mechanism. Finally, the main process input correlations with the obtained results were detected and reported.
Effect of material properties and process parameters on quality of friction stir forming
Gagliardi F.;Ambrogio G.;
2021-01-01
Abstract
Friction stir forming is a joining process that can be employed for different types of mechanical connections. The idea is to deform one material and mechanically interlock with a second material exploiting an enhanced ductility at elevated temperature resulting from stir heating. A rigid rotating tool is plunged and, subsequently, moved in a parallel direction to the plane of the upper sheet pushing the material into holes or grooves of the part, placed below, to be joined. Herein, experimental tests were executed by changing the main process variables with the aim of highlighting their effects on the material flow during the studs' extrusion. An aluminum alloy of the same chemical composition, but with two different heat treatments, was processed pointing out the influence of the alloy's mechanical properties on the process dynamics and final stud integrity. An evolution of the microstructure as a result of the process thermo-mechanical conditions is also provided. Furthermore, a full design of experiments was executed to highlight the influences of analyzed input parameters on the stud dimensions. The cross-section area of each extruded stud was measured and analyzed for the joint interlocking mechanism. Finally, the main process input correlations with the obtained results were detected and reported.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.