Investigating the influence of deposition techniques and processing conditions on AA2024/SiC FSW joints: Evaluation of microstructural and mechanical properties

Abstract

Friction Stir Welding (FSW) has become a mature technology for most metal alloys. The current frontier is the development of in-situ alloyed or reinforced materials to further spread the field of application of this technique. In the paper, SiC-reinforced 2024-T3 aluminum joints were produced by integrating micro-size SiC particles by creating proper features in the sheets. A new joint design was proposed in order to overcome the issues of powder dispersion occurring with the more conventional hole design. The influence of distinct parameters viz., tool rotation speed, traverse speed, and joint configuration on SiC dispersion, microstructure, and mechanical properties of the prepared joints has been corroborated. Standard FSW was also carried out for comparison. The rotation and travel speeds varied ranging 700–1100 rpm and 50–90 mm/min, respectively. The distribution of reinforcement particles in various zones of the FSW process was examined by using optical microscopy (OM) and scanning electron microscopy (SEM). It was found that the velocity ratio variation influences the heat generation and thereby the microstructural and mechanical properties owing to distinct SiC particulate dispersion throughout the joint area. The welded joints produced at the 1100 rpm and 70 mm/min (S1100–70) combination exhibit an increment in hardness by 30 % as compared to base material resulting from grain size reduction and better dispersion of SiC powder. Finally, the analysis of power consumption and temperature during the process was carried out. These additional measurements were crucial in determining the overall performance and feasibility of using SiC powder in the welding process.