Friction stir welding process of high entropy alloys: Current status, challenges and future perspectives

High-entropy alloys (HEAs) have attracted great attention because they provide diversified possibilities for developing interesting new alloys with many exceptional properties. Welding is one of the most important processes for newly developed metallic alloys moving toward engineering applications. As a solid-state welding method, friction stir welding (FSW) exhibits unique advantages in a similar joining of HEAs and dissimilar joining between HEAs and other alloys, thus arousing widespread research interest. This chapter provides an overview of the recent progress in the FSW of HEAs. Particular attention and critical assessment have been given to the weldability, the microstructure evolution and mechanical properties of the resulting joint, and their affecting factors, such as initial state, welding parameter, additional cooling, and tool wear. Finally, on the basis of the up-to-date status, we put forward our views and prospects for future work, aiming to provide a basis for researchers in this field. © 2024 Elsevier Inc. All rights are reserved including those for text and data mining AI training and similar technologies.