External energy field assisted friction stir welding (FSW) is an improved solid-phase welding method that is widely used in aerospace

automotive manufacturing

and energy industries. By introducing external energy

the microstructure and properties of the joint can be improved

thereby enhancing the welding quality and efficiency. This article classifies external energy field-assisted FSW techniques

summarizes the selection and control of energy fields

optimization of process parameters

and summarizes the effects of external energy fields on welding temperature

axial load

and joint microstructure and properties. Finally

this article summarizes the future development trends of external energy field-assisted FSW technology.