“…2,3 Over the past few decades, various methods have been proposed to apply severe plastic strain to metal materials and convert their structure into very fine-grained or nanostructure. Some of these methods are: equal-channel angular pressing, 4,5 SPD processes using extrusion, [6][7][8] twist extrusion, 9,10 accumulative roll bonding, 11,12 and constrained groove pressing (CGP). [13][14][15] The CGP process, which is the subject of this research, is an efficient method for severe plastic deformation of sheets that has been considered by researchers in recent years.…”