Influence of Process Parameters on Microstructure and Mechanical Properties in AA2024-T3 Friction Stir Welding

Material stirring and heat generation in friction stir welding processes induce significant microstructure and material properties alterations. Previous studies high- lighted the relationship among microstructure, grain size, microhardness, and performance of the joint. In this con- text, an opportune definition of process parameters, in particular rotating and welding speed, is crucial to improve joint reliability. In this article, results provided by a numerical and experimental investigation on the influence of rotating and welding speed on microstructure, mechan- ical properties, and joint quality in AA2024-T3 friction stir welded butt joints are reported. Experimental data are presented and discussed considering numerically computed temperature and strain rate distributions, providing useful information for parameters setting. Processing window, i.e., parameters resulting in a successful material deposi- tion, is also individuated.