Table 4.

Advantages of the FSW/FSP technique.

Metallurgical characteristics	Mechanical Properties	Energy	Safety	Environmental	Reference
Fine and ultra-fine microstructure, Texture modification	High tensile strength and good ductility	Lower required energy for welding and favorite joint efficiency	No fumes and welding arc	Annihilation of grinding wastes and solvents for degreasing	[2,26,27,28,80,113,114]
Absence of welding and casting defects	High fracture toughness and energy absorption	Use of smaller thicknesses due to increased strength of welded material	No spatter	Not required to the shielding gas	[2,26,27,28,80,113,114]
Excellent distribution of alloying elements and precipitations and their dissolution in the matrix phase	High fatigue strength	Reduction of structure weight due to using smaller thicknesses	No spark	Not required to the surface cleaning	[2,26,27,28,80,113,114]
Good microstructural homogenization	High wear resistance	Lower consumption of fuel caused by weight reduction of structure in industries of automobile, aircraft, etc.	No radiation of ultraviolet	More decrease in production of CO2 gas due to lower fuel consumption	[2,26,27,28,80,113,114]