Document Type: Research Paper

Authors

1 Department of Manufacturing and Production Engineering, Faculty of Mechanical Engineering, University of Tabriz, Tabriz, Iran

2 Department of Manufacturing and Production Engineering, Faculty of Mechanical Engineering, University of Tabriz, Tabriz, East Azarbayjan, Iran

3 Urmia University of Technology, Mechanical engineering department

10.22061/jcarme.2019.4829.1589

Abstract

In recent decades, the industrial applications of refined grained pure copper and its alloys have been expanded. The properties such as high strength, high density and low deformability make these alloy more attractive. Hence, investigating the fracture mechanism of refined grained copper is of great significance. In this study, the fracture analysis of copper was investigated using the equal channel angular pressing process. Experimental results on metal alloys have demonstrated that stress state should be incorporated in the constitutive equations. Therefore, the fracture process was analyzed here by focusing on its relationship with the Lode angel variable. To prepare the ECAPed specimens, a die set was manufactured and tensile strength tests were carried out on dog-bone and notched flat plate specimens up to fracture. In addition, the mean value of grain sizes of the copper specimens were evaluated. The results demonstrate that the grain refining process profoundly enhances the load carrying capacity of copper specimens. Moreover, the dog-bone tensile tests clearly show that the peak value of the strain hardening in refined grained copper occurs up to two passes and after two passes the strain hardening drops. Furthermore, the results reveal that the Lode angel variable have a significant influence on the failure of the refined grained copper specimens.

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