Recent research progress in friction stir welding of aluminium and copper dissimilar joint: a review

Aluminium and copper are employed in various industrial applications due to their high plasticity, thermal conductivity, electrical conductivity and characteristics. By effectively joining dissimilar aluminium and copper, the unique properties of composite formed by these metals can be adequately addressed. Friction stir welding (FSW), an energy-efficient solid-state welding process is capable of joining dissimilar metals, has enormous potential in the future of various industries. This present work comprehensively summarises all pertinent topics related to aluminium to copper FSW, such as FSW process parameters, microstructural characterisation, mechanical properties, and electrical characteristics of aluminium–copper joints produced by FSW. In addition, the current report also discusses several applications of additives used in dissimilar FSW of Al–Cu and new FSW techniques, which generally aim to enhance Al–Cu joint properties. Moreover, numerical modelling of Al–Cu FSW is discussed profoundly to understand the effects of alterations in different process parameters on temperature gradients and microstructure evolution, which would be time-consuming or prohibitively expensive in practice by physical testing. Additionally, several recommendations for future research are proposed to facilitate the advancement and success of Al–Cu FSW studies.