Papers by Keyword: Finite Element (FE) Simulation

Abstract: Based on the finite element analysis software AdvantEdge, a simulation model for the milling process of aluminum alloy 7075-T7451was established to research the cutting temperature. This simulation model predicts the temperature distribution of work-piece and cutting tool, and the temperature variation trend along with the milling speed and rotational speed. The simulation results provide valuable references for researching on machining mechanism.

Abstract: One-axle rotary shaping with the elastic medium (RSEM) is a kind of advanced sheet metal forming process. The research object is the springback of aluminous U-section. The orthogonal method is used to arrange the simulation experiments, the forming and springback of the workpiece are simulated successfully with the Finite Element Simulation software, and The main factors influenced the RSEM are analyzed. The simulation results are used as the training samples of the artificial neural network (ANN), and the ANN prediction model of RSEM process is set up. The prediction results would be tested with the experiment data, and only a little tolerance was existed between the two values. It demonstrated that the combination of orthogonal test, numerical simulation and neural network could effectively predict the springback of RSEM, the design efficiency of process parameters would be improved. It would guide the development of precision forming technology.

Abstract: Nowadays the immature of the precise synchronizer gear ring processing method have greatly impeded the development of the vehicle business in China. The extrusion process is a very important procedure in making precise synchronizer gear ring, but there is not any introductive and effective research yet to the issue of the optimal processing parameter in precise synchronizer gear ring procession. This research provides several processing parameters in precise synchronizer gear ring procession by means of simulating the processing in DEFORM-2D software and trying it in reality. The result shows that the whole three processing procedures have influence in the result of the gear ring. The second procedure is the most influential, followed by the fist procedure. Adjustment can be effectively conducted on the product of the first procedure by changing the fillet radius of the top die and the bottom die, R1, R2; adjustment can be effectively conducted on the product of the second procedure by changing the fillet radius of the top die and the bottom die and the angle of the upper inclination of the top die,α2. The result of this paper gives an instruction in precise synchronizer gear ring procession.

Abstract: The springback phenomenon of thick freeform surface steel plate forming occurs consequentially after unloading, which reduces the accuracy of the parts manufacturing and the processing efficiency. This paper developed a numerical simulation solution to the springback of thick freeform surface parts forming process using PAM-STAMP 2G at 20°C, 200°C, 400°C, 600°C, 700°C and 800°C, respectively. The maximum springback value of freeform surface parts decreases with increasing temperature, at 600°C, the minimum extreme value, and then the value with increasing temperature continues to rise higher. PAM-STAMP 2G offers a Die Compensation module, which is used to modify the die surface of thick freeform surface steel plate forming focused on springback defects. The approach based on iteratively comparing a target part shape with a numerical simulated part shape following forming and springback can be effective in reducing springback error. With it, the new tooling shapes will ensure the geometric accuracy of the thick freeform surface parts.

Abstract: In this paper, the initial residual stress field for titanium alloy monolithic component blank is simulated and analyzed by applying a sequentially coupled thermal and mechanical procedure based on finite element method. The control equation of heat conduction of annealing process is studied, and the boundary condition and fundamental equations of simulation are given. The research results show that the initial residual stress field for titanium alloy monolithic component blank radiates from the center region to outside, the center region being the maximum value, then decreases gradually, until a minimum value is attained at the corner.

Abstract: Flow stress is a vital input data for machining simulations, which is experimentally measured from Split Hopkinson pressure bar (SHPB) tests. However such flow stress does not fit machining conditions of strain, strain rate and temperatures and lead to serious simulation errors. In this research work an integrated Taguchi – Finite element (FE) methodology is adopted to optimize the flow stress of AISI 1045 steel material for orthogonal machining. The flow stress computed from the optimization approach along with thermo physical material properties are input into the FE code. The FE cutting forces and chip thickness ratio (CTR) showed an improvement of 6-8% and 2-4% over conventional Johnson – Cook (JC) models. An optimum set of JC model parameters were found from the study. The JC parametric analysis indicated high cutting force sensitivity to yield strength and CTR sensitivity to yield strength, strain hardening and thermal softening.

Abstract: Tube bending is a complex process with multi-factor coupling effect and multiple defects occurring. The wall thinning, as one of the important defects in tube bending, determines the bending quality. In this study, taking thin-walled 6061-T4 Al-alloy tube with Φ50.8×t0.889×R101.6mm (outer diameter D × wall thickness t × bending radius R) as the objective, the significance of processing parameters on the wall thinning degree is studied using the orthogonal test under ABAQUS/Explicit platform. The results show that: 1) the bending radius, the clearance between the tube and the pressure die, the friction between the tube and the pressure die, the clearance between the tube and the pressure die, the clearance between the tube and the mandrel and the friction between the tube and the mandrel affect the wall thinning significantly, while the coefficient of boost velocity, the number of mandrel balls, the friction between the tube and the wiper die, the mandrel extension length and the friction between the tube and the bending die have little effect on the wall thinning degree.

Abstract: The rear part of the APF A380 has a deep drawn shape. In order to develop the forming by SPF process of this part, numerical simulation by finite elements has been performed. Several configurations for 2D and 3D modeling were studied to determine an efficient forming strategy. A double-action solution was chosen. It ensures a satisfactory thickness distribution. This article will deal with the modeling assumptions, the results of individual cases of calculation and comparison with parts obtained at the Airbus plant.

Abstract: In the superplastic process, the non-uniformity of the produced part thickness and the possibility of severe thinning are among the major disadvantages. This paper presents a parametric study on the superplastic forming of a Pb-Sn sheet into the shape of a long rectangular pan. A two dimensional plain strain finite element model was used to predict the forming times and thinning profiles of the formed Pb-Sn pan. The effect of varying the sidewall inclination angle was investigated for different friction conditions at the die-sheet interface. Results showed that increasing the side wall inclination angle reduced the forming time and provided a better thickness distribution.

Abstract: The expanded diameter conductors are widely used for high voltage electricity power transmission due to its superior ability to prevent electronic corona phenomenon. However an undesired stability problem of wire distribution configuration within the cross-section of the conductor often occurs during the power line stringing processes, especially for the not-well-designed conductor structures. This phenomenon is typically characterized by the appearance of outer wire/wires jumping out of the layer; therefore it is also referred as wire jump-out problem. Finite element model which can predict the wire jump-out phenomenon has been successfully developed in this research project. Series of stimulations have been carried out to investigate the key factors to cause the wire jump-out problem. The reduction of radial distances between the adjacent aluminum wire layers due to the obvious indentation deformation at the trellis contact points were identified to be one of the most significant factors to lead to the wire jump-out problem. Numerical results show that keeping sufficient initial gap between the adjacent outer layer wires in the initial design can be a simple effective way to relieve/avoid the wire jump-out problem.