Schematic diagram of metal matrix composite fabrication by friction stir processing. Reproduced from International Journal of Precision Engineering and Manufacturing, Material properties of graphene/aluminum metal matrix composites fabricated by friction stir processing, 15, 2014, 1235–1239,⁷⁹  C.-H. Jeon, Y.-H. Jeong, J.-J. Seo, H. N. Tien, S.-T. Hong, Y.-J. Yum, S.-H. Hur and K.-J. Lee, © KSPE and Springer 2014, with permission of Springer.