Effects of the Geometric Profile of Twist Channel Angular Pressing (TCAP) on the Deformation Behaviors and Microstructure Evolution of AL7050 Alloy

Document Type : Original Research Paper


1 Department of Mechanical Engineering, Faculty of Engineering, K.N. Toosi University of Technology, Tehran, Iran.

2 Department of Mechanical Engineering, Faculty of Engineering, Shahrekord University, Shahrekord, Iran.

3 Department of Mechanical Engineering, Faculty of Engineering, Malayer University, Malayer, Iran.


 Severe plastic deformation processes are used as a method to increase the mechanical strength of metals. One of the new deformation methods is twist channel angular pressing (TCAP). TCAP has been developed based on a combination of twist extrusion processes (TE) and Equal Channel Angular Pressing (ECAP) process. In this paper, the effect of TCAP die geometry on the grain size distribution and plasticity properties using simulation in DEFORM software is investigated. For this reason, dies with internal angles of 90, 100 and 110, external (corner) angles of 0, 10 and 20 and twist angles of 30, 45, 60 are used. In addition, the location of the twist channel is examined before and after the ECAP location. The distribution of plastic strain, grain size distribution, and the required punch force for the TCAP process on Aluminum alloy 7050 are extracted in all conditions. The results showed that locating the twist section after ECAP location led to a better microstructure in the billet. Also, die with a twist angle of 45, an internal angle of 110, and a corner angle of 0 created the best results; therefore, the grain size decreased from 100µm to 3.67µm. 


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