“…porosity, cracking, blow holes which appear during conventional fusion welding process are avoided (Cavaliere, 2013;Kevorkijan, 2002;Khodaverdizadeh, Mahmoudi, Heidarzadeh, & Nazari, 2012;Kundu & Singh, 2016;Taban & Kaluc, 2006). In friction stir welding, high temperature below the melting point is attained through friction between tool shoulder and joining sheets as well as frictional heat produced by tool pin and the semi-solid material through the plastic flow of materials under the tool shoulder.…”