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In this paper, a new application of equal channel angular pressing (ECAP) for fabrication of Cu–Al bimetallic tubes is presented. For the evaluation of ECAP effects, the microstructure and micro-ha...

Equal channel angular pressing (ECAP) is a type of severe plastic deformation procedure for achieving ultra-fine grain structures. This article investigates artificial neural network (ANN) modeling of ECAP process based on experimental and three-dimensional (3D) finite element methods (FEM).In order to do so, an ECAP die was designed and manufactured with the channel angle of 90° and the outer corner angle of 15°. Commercial pure aluminum was ECAPed and the obtained data was used for validating the FEM model. After confirming the validity of the model with experimental data, a number of parameters are considered. These include the die channel angles (angle between the channels Φ and the outer corner angle Ψ) and the number of passes which were subsequently used for training the ANN. Finally, experimental and numerical data was used to train neural networks. As a result, it is shown that a feed forward back propagation ANN can be used for efficient die design and process determination in the ECAP. There is...

Forming limit diagram (FLD) provides the limiting strains a sheet metal can sustain whilst being formed. In this article, the formability of Ti6Al4 V titanium alloy and Al6061-T6 aluminum alloy sheets is investigated experimentally using hydroforming deep drawing. Hecker's simplified technique [1] was used to obtain experimental FLDs for these sheet materials. Artificial neural network (ANN) modeling of the process based on experimental results is introduced to predict FLDs. It is shown that a feed forward back propagation (BP) ANN can predict the FLDs, therefore, indicating the possibility of ANN as a strong tool in simulating the process. According to comparisons there is a good agreement between experimental and neural network results.

A simplified sheet hydroforming tooling was designed, fabricated, and tested. The advantage of the new tooling is its simplification of the tools, its requirement of lower hydraulic pressure for forming and decreasing the cost of the process. In this article, a new method of hydroforming deep drawing assisted by floating disk is proposed and investigated through experiments and simulation. Moreover, its advantages, such as simplifying the tools, decreasing the required medium pressure of the forming process, and elimination of some wrinkle due to ironing effect, have been discussed. An aluminum alloy, Al6061-T6, is formed successfully, and the influence of process parameters including the punch nose radius and friction are studied. It is determined that decreasing punch radii and friction, lead to a decrease in initial pressure and an increased safe zone, respectively. Working pressure curves, which guarantee sound workpieces, have been founded by series of experimental results. Wrinkling and fracture mod...

Fine-blanking (FB) is an effective and economical shearing process that offers a precise and clean cutting-edge finish, eliminates unnecessary secondary operations, and increases quality. In the traditional blanking product development paradigm, the design of the formed product and tooling is usually based on know-how and experience, which are generally obtained through long years of apprenticeship and skilled craftsmanship. In this study, the possibility of using finite element method (FEM) together with artificial neural networks (ANN) was investigated to analysis the fine-blanking process. Finite element analysis was used to simulate the process with an isotropic elastic–plastic material model. The results compare well with experimental results available in the literature; after confirming the validity of the model with experimental data, a number of parameters such as V-ring height effect, punch and holder force on die-roll, hydrostatic pressure status as an important factor in increasing burnish zone...