Process Force Reduction During Robotic Friction Stir Welding of Aluminum Alloys with Reduced Tool Aspect Ratios

摘要

Friction Stir Welding has increasingly been gaining relevance for joining nonferrous metals, especially aluminum alloys. However, when considering FSW as an alternative for conventional processes, some characteristics of FSW like high process forces and clamping requirements still represent drawbacks regarding accessibility and work piece loading capacity. The tendency towards lightweight design and more complex components amplifies this challenge. Therefore, the objective of this investigation is to evaluate the scaling effects during FSW with reduced tool diameters at adjusted process parameters, in order to keep the shear stress conditions in the shear layer constant and hence counteract the compromised mechanical loadability of the scaled tools. The experiments in this investigation are carried out for EN AW 5754 H12 with a material thickness of 2 mm. The results demonstrate the potential to decrease the axial force by reducing the material volume displaced by the pin and hence reduce the load on the workpiece and the required spindle torque.