Single point incremental Forming is a sheet metal Forming process that has more flexibility than another method. These processes don’t require to die and could formed various shape white use the simple tool and CNC machine. In this paper the influence of process parameters on the forces and dimensional accuracy and thickness distribution in single point incremental Forming is investigated. These parameters include the feed rate, tool rotation, vertical step, movement strategy of tool and lubrication. Beginning with the design and construction of the fixture and clamping it on the dynamometer and create of tool (tungsten carbide), the preparation process was done on a CNC milling machine. Then, the experimental tests were carried out on Aluminum alloy sheets (Al-1200) with creation of pyramid frustum; after the measuring of force in different directions, the influence of parameters on the Forming force was investigated. Also parts were measured with CMM devices and compared. The results showed that with increasing the feed rate, the vertical force decreases and with increasing tool rotation speed, horizontal force decreases. The use of lubricant, is effective on the improvement of process.

Two-Point Incremental Forming (TPIF) method is a novel technique for producing free form shell parts. The main purpose of this study is to analyze the TPIF process, and, by approximate calculation, to find the force applied to the tool. One of the limitations of an incremental Forming process is that during this process force applied to the tool is born by the machine. In this research, an equation for approximate prediction of the force applied to the tool is presented using the values of the yield stress of the sheet, friction coefficient, tool radius and thickness of the sheet; hence, the applied force can be calculated. By increasing the Forming angle, the amount of the created local strain increases and the change in thickness and the force applied to the tool is enhanced. However, by increasing the angle of punch wall, less compressive stress is applied to the metal sheet due to the reduction in contact between the surface of the tool and punch wall. Analytical equations presented are validated by the results from experimental tests.

In this study, an artificial neural network was used to predict the minimum force required to single point incremental Forming (SPIF) of thin sheets of Aluminium AA3003-O and calamine brass Cu67Zn33 alloy. Accordingly, the parameters for processing, i. e., step depth, the feed rate of the tool, spindle speed, wall angle, thickness of metal sheets and type of material were selected as input and the minimum vertical force component was selected as the model output. To train the model, a Multilayer perceptron neural network structure and feed-forward backpropagation algorithm have been employed. After testing many different artificial neural network (ANN) architectures, an optimal structure of the model i. e. 6-14-1 was obtained. The results, with a correlation relation between experiments to predicted force,-0. 215 mean absolute error, show a very good agreement.

The blank-holder force is an important and influential parameter in the sheet metal Forming process. The size of this force around the part can be very effective in eliminating the defects of fracture and wrinkling in different points of the part. In symmetrical axial parts, a suitable uniform blank-holder force can prevent both defects, but for asymmetric axial parts, it is usually difficult to achieve a suitable uniform blank-holder force. In this case, the non-uniform blank-holder force can have a significant effect on improving the quality of parts. It is clear that simulation of the sheet metal Forming process in finite element software and the effective use of optimization algorithms can be of great help in determining the amount of non-uniform blank-holder force. In this research, a method for automatic determination of non-uniform blank-holder force is presented. In this method, which has been created with the help of Catia, Abaqus, and Modefrontier software, various simulations and change of input parameters are performed completely automatically, until the appropriate conditions for sheet metal Forming are determined. To show how this method works, two pieces with different geometries were examined. In these two geometries, it was not possible to achieve a piece without fracture and wrinkling with uniform blank-holder force, but the results showed that using this method, a suitable non-uniform arrangement of blank-holder force can be achieved automatically, which produces a flawless piece.

Single point incremental sheet Forming is a die-less Forming technology in which the sheet metal is formed progressively by the movement of a tool in the specified path. In this paper, the single point incremental Forming of the AA3105-St12 two-layer sheet is studied through numerical and experimental approaches. Numerical simulation of the process is done based on the finite element method. The validity of the numerical model is evaluated via a comparison between the obtained numerical and experimental results. The force applied to the Forming tool, the thickness distribution of formed sheets, and the maximum thinning that occurred in aluminum and steel layers were studied. The effects of the parameters of the two-layer sheet including total thickness, thickness ratio of layers, and arrangement of layers were investigated as well. The results showed that regardless of the contact of the steel or aluminum layer with the tool, increasing the ratio of the thickness of the steel layer to the thickness of the aluminum layer reduces the thinning in the aluminum layer and increases it in the steel layer. Hence, thinning becomes more severe in each layer when it is in contact with the Forming tool.

In this paper, torsion extrusion (TE) process on 1050 aluminum alloy (AA) was investigated by simulation as a severe plastic deformation (SPD) method and the effects of friction coefficient, angular velocity of the rotating die and punch speed on maximum punch force were studied. A finite element (FE) model was developed to simulate the TE process via DEFORM software. The FE results were validated compared with experimental results and then the FE model was used for implementing the set of simulations designed by Taguchi’ s L9 orthogonal array. Maximum punch force was determined and put into signal to noise (S/N) ratio and the analysis of variance (ANOVA) techniques to specify the importance and contribution of parameters. The results indicated that the friction coefficient has the most effect on maximum punch force and effects of the angular velocity and punch speed are not sensible. Results analysis represented that maximum punch force enhances by increasing the friction coefficient. Moreover, friction coefficient of 0. 18, angular velocity of 0. 11 rad/s and punch speed of 0. 2 mm/s lead to the minimum punch force.

Present study describes the approach of applying Multi-Objective optimization method to optimizing of sheet metal Forming Die. In many studies, Finite element analysis and optimization technique have been integrated to solve the optimal process parameters of sheet metal Forming by transForming multi-objective problem into a single-objective problem. This paper aims to minimize the objective functions of fracture and wrinkle simultaneously. Design variables are blank-holding force and draw-bead geometry. Response surface model has been used for design of experiment and finding relationships between variables and objective functions. In designing of experiments v-optimal design has been used which minimizes the average prediction error variance, to obtain accurate predictions. Forming Limit Curve has been used to define the objective functions. Finite element analysis applied for simulating the Forming process. Proposed approach has been investigated on a drawing part and experimentally verified. The optimal design showed a good agreement with experimental species. It has been observed that proposed approach provides aneffective solution to design of process parameters without a the ‘trial and error’ procedure.

The optimal Forming of the metallic parts with the lowest required Forming force has always been the focus of researchers. In this paper, effective parameters in hydrodynamic deep drawing assisted by radial pressure of cylindrical cups with a flat head with minimum required Forming force have been investigated. At first, the necessary experiments were designed using the fractional factorial design of experiment. In this design, maximum fluid pressure, punch velocity, punch nose radius, friction coefficient between punch and sheet, friction coefficient between die and sheet, and die entrance radius were considered input variables. An experimentally validated finite element model was used for perForming the designed experiments and extracting the maximum punch force for each experiment. Finally, by using analysis of variance, the main and the interaction effects of the parameters on the maximum punch force were determined. Results showed that the maximum fluid pressure and punch nose radius have the highest influence on the maximum punch force. Decreasing the maximum fluid pressure from 39 to 15 MPa, leads to a decrease of 55% in the maximum punch force. Also, by reducing the punch nose radius from 10 to 2 mm, the maximum punch force decreases by 55%.