An investigation into the effective parameters in optimal design of ECAP-Conform process of commercially pure titanium using statistical and numerical approaches

Document Type : Article

Authors

1 Department of Mechanical Engineering, University of Birjand, Birjand, Iran

2 Faculty of Mechanical and Mechatronics Engineering, Shahrood University of Technology, Shahrood, P.O. Box 3619995161, Iran

Abstract

The Equal Channel Angular Pressing-Conform process has improved the mechanical and functional properties of materials as well as resolves the disadvantages of conventional ECAP. The main goal of this study was investigation of the variable in ECAP-Conform process of pure titanium Grade 2. The design of experiments with full factorial technique was implemented in conjunction with finite element numerical simulation. The equivalent plastic strain, required torque, applied force on the ECAP die, and the warping radius of the product were measured and results were interpreted using analysis of variance. It was found that the ECAP die angles and the rod bending angle have the highest effect on both imposed strain and required torque. Also, the rod bending angle and the rod-die friction had no significant effect on the warping radius. The optimal values were specified for minimizing the required torque, reaction force, and warping radius, and maximizing the imposed strain. Based on the optimal estimated parameters, the minimum values of torque, force, warping radius, and maximum value of equivalent strain were predicted to 8.4 kN.m, 42 kN, 0.36 m, and 1.7, respectively. Also, the response optimizer obtained the results with less than 8% error in comparison with numerical simulation.

Keywords


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