Table of Contents

This article has been retracted as it is essentially identical in content with the published article “Elucidating of rotation speed in friction stir welding of pure copper: Thermal modeling” published in Computational Materials Science, Volume 81, January 2014, Pages 296–302.

View the full Retraction here.


  1. M. Jabbari and C. C. Tutum, “Optimum rotation speed for the friction stir welding of pure copper,” ISRN Materials Science, vol. 2013, Article ID 978031, 5 pages, 2013.
ISRN Materials Science
Volume 2013, Article ID 978031, 5 pages
Research Article

Optimum Rotation Speed for the Friction Stir Welding of Pure Copper

1Department of Mechanical Engineering, Technical University of Denmark, Nils Koppels Allé, 2800 Kongens Lyngby, Denmark
2Department of Computer and Electrical Engineering, Michigan State University, East Lansing, MI 48824, USA

Received 24 June 2013; Accepted 14 July 2013

Academic Editors: S. Kirihara and S. Li

Copyright © 2013 Masoud Jabbari and Cem C. Tutum. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The friction stir welding (FSW) was conducted in the pure copper plates with the thickness of 4 mm in the constant traverse speed of 25 mm/min and five different rotation speeds. Analysis of metallographic images showed that the increasing of the rotation speed results in the increase of grain size in the nugget zone. Vickers hardness tests were conducted on the weld samples and the maximum hardness obtained in rotation speed of 900 rpm. Results of the tensile tests and their comparison with that of the base metal showed that the maximum strength and the minimum elongation are achieved again in this rotation speed. Yield strength and ultimate tensile strength increased with the decrease in grain size in the nugget region, and the yield strength obeyed Hall-Petch relationship. Hence, the hardness values do not follow the relationship.