International Journal of Mechanics and Applications
pISSN: 21659281 eISSN: 21659303
2017; 7(1): 113
doi:10.5923/j.mechanics.20170701.01
Madaraka Fredrick Mwema^{1}, Kiptoo Mathew^{1}, Shagwira Harrison^{1}, Obiko Japheth^{2}
^{1}Mechanical Engineering Department, Dedan Kimathi University of Technology, Nyeri, Kenya
^{2}Mining, Materials and Petroleum Engineering Department, Jomo Kenyatta University of Agriculture & Technology, Nairobi, Kenya
Correspondence to: Madaraka Fredrick Mwema, Mechanical Engineering Department, Dedan Kimathi University of Technology, Nyeri, Kenya.
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Copyright © 2017 Scientific & Academic Publishing. All Rights Reserved.
This work is licensed under the Creative Commons Attribution International License (CC BY).
http://creativecommons.org/licenses/by/4.0/
The purpose of this work is to optimize angular extrusion for sever plastic deformation of tubular specimens. A finite element model (FEM) was built in Deform3D^{®} for three extrusion dies and analyzed. The dies were ECAP (135°), TCAP with external groove of 90° (denoted as TCAPe) and TCAP with internal groove of 90° (denoted as TCAPi). The analysis for process parameters (such as coefficient of frictionµ, die anglesѱ and φ, temperature  T, and radius ratioR) showed that TCAPi was the optimal die in processing Al6063 tubes based on strain and load distribution of the model.The TCAPi die model was further optimized for different parameters namely die angles, coefficient of friction, deformation ratio and temperature. The results showed that at constant process temperature of 25°C, the optimal TCAPi has the following parameters: φ_{2}_{}= 80°, Ψ_{1}_{ }= 30°, Ψ_{2}_{ }= 80°, Ψ_{3}_{ }= 30°, µ = 0.4 and R = 1.5.
Keywords: ECAP, Tubular channel angular pressing (TCAP), Finite element, Severe plastic deformation, Strains
Cite this paper: Madaraka Fredrick Mwema, Kiptoo Mathew, Shagwira Harrison, Obiko Japheth, Design Optimization of Angular Extrusion for Severe Plastic Deformation of Tubular Specimens, International Journal of Mechanics and Applications, Vol. 7 No. 1, 2017, pp. 113. doi: 10.5923/j.mechanics.20170701.01.
Figure 1. Effective plastic equivalent strain contours for SPD processing to Al6063 tubes through (a) ECAP (b) TCAPe and (c) TCAPi 
Figure 2. Effective equivalent strain versus distance (mm) from the internal thickness of the tube after processing through (a) ECAP (b) TCAPe and (c) TCAI dies 
Figure 3. Pressing load versus time during (a) ECAP (b) TCAPe and (c) TCAPi processing 
Figure 4. Die configuration and process parameters 

Figure 5. Effective plastic equivalent strain contours for TCAPi for Al6063 tubes processed through (a) A (b) B (c) C (d) D (e) E dies 
Figure 6. Effective strain versus distance across the thickness of the tube after processing through (a) A (b) B (c) C (d) D (e) E dies 
Figure 7. Pressing load versus time for (a) A (b) B (c) C (d) D (e) E dies 