Mohammad-Kazem Besharati-Givi is an associate professor at University of Tehran, School of Mechanical Engineering. He received his PhD degree from the University of Leeds in 1990. He is an expert in metal forming and welding, particularly FSW/FSP, and has published more than 50 ISI papers in the field of FSW/FSP.Parviz Asadi is a PhD student at University of Tehran, School of Mechanical Engineering. He was selected as the best student researcher at the University of Tehran in 2010 and has published 15 ISI papers in the field of FSW/FSP.