Modares Mechanical Engineering

Modares Mechanical Engineering

Optimization and investigation of effective parameters in ECAP-Conform process using response surface method, case study: AA7075 rod

Document Type : Original Research

Authors
Sadegh Moradi 1
Mahdi Gerdooei 2
Hasan Ghaforian Nosrati 3
Seyyed Mojtaba Varedi-Koulaei 4
1 MSc graduated from the faculty of mechanical engineering, shahrood university of technology
2 Associate Professor Faculty of Mechanical And Mechatronics Engineering
3 Instructor, Department of Mechanical Engineering, Esfarayen University of Technology
4 Assistant Professor Faculty of Mechanical And Mechatronics Engineering
Abstract
The ECAP-Conform is one of the newest and less known processes that improve mechanical properties. In the present study, the effective parameters of the ECAP-Conform process for AA7075 have been investigated. Influence of parameters such as roller radius, bending angle, die channel angles, rod/roll friction coefficient, rod/die friction coefficient, and the aspect ratio of the die groove on the torque, the applied force on the die, the stress, and the effective plastic strain, the output rod curvature, and the strain distribution uniformity have been investigated. The design of experiments was carried out based on the response surface method by the Minitab software, and simulations were performed using the ABAQUS software. To validate the FEM, the ECAP-Conform process of AA7075 rod was performed and the comparison of experimental and numerical results have acceptable compliance (7.5% error). It was found that the die channel angles and the rod/die friction coefficient have a more significant effect on all responses. Moreover, to maximize the imposed strain and strength, and to minimize the process torque and curvature, as well as achieving a uniform distribution of strain, the optimal output parameters have been obtained.
Keywords
ECAP-Conform
AA7075
simulation
Optimization
Response surface method

Subjects

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Modares Mechanical Engineering
Volume 22, Issue 1
December 2021
Pages 57-70