<div> Friction-stir welding (FSW), a relatively new joining process, is a solid-state joining technique that is energy efficient, environmentally friendly, and versatile. Friction-stir processing (FSP) is an emerging processing technique based on FSW principles. The book is structured into ten chapters covering applications of the technology: tool and welding design, material and heat flow, microstructural evolution, mechanical properties and corrosion behavior and wear properties. Later chapters cover mechanical alloying and FSP as a welding and casting repair technique, optimization and simulation of artificial neural networks, and FSW and FSP of polymers.</div>