Springback Analysis of Sheet Metals Regarding Material Hardening

2005 ◽  
Vol 6-8 ◽  
pp. 721-728 ◽  
Author(s):  
Marco Schikorra ◽  
R. Govindarajan ◽  
Alexander Brosius ◽  
Matthias Kleiner
Keyword(s):  
Finite Element ◽  
Finite Element Simulation ◽  
Dimensional Accuracy ◽  
Material Behavior ◽  
Experimental Investigations ◽  
Sheet Metals ◽  
Forming Process ◽  
Element Simulation ◽  
Strain Reversal ◽  
Draw Bending

The phenomenon of springback of thin-walled sheet metal parts after forming is a well known problem of forming technology in general, but particularly since the finite element simulation offers the opportunity to predict geometrical and material properties after forming. Irrespective of the intensive efforts in the previous years, a reliable and accurate prediction of springback deviations by use of the finite element simulation is still not possible. This paper deals with the numerical and experimental analysis of the springback effect itself, which dependents on the final stress states of a part after the forming process. Experimental investigations have been carried out to analyze geometrical accuracy in loaded and unloaded conditions to isolate the springback effect. Additional finite element simulations have been conducted in order to compare the experimental and numerical results and to determine the geometrical differences and their reasons. Two experimental set-ups are being discussed: Air bending on the one hand, which offers good access to the specimen in the testing equipment, and draw bending on the other hand, which is characterized by a simple strain state, but also by strain reversal within the tests. Both experiments were carried out using DP600 and X5CrNi18.10 with three different sheet thicknesses and bend radii and were compared with according FE-models. An additional shear test experiment has been developed to characterize the material behavior of the tested sheet metals for strain reversal. Furthermore, the importance of the Bauschinger effect and usable hardening models were analyzed. This study intended to investigate reasons for insufficient form and dimensional accuracy between simulations and experiments after springback and to propose modeling methods to improve the accuracy.

Texture Based Finite Element Simulation of a Two-Step Can Forming Process

2012 ◽  
Vol 504-506 ◽  
pp. 655-660 ◽  
Author(s):  
Vedran Glavas ◽  
Thomas Böhlke ◽  
Dominique Daniel ◽  
Christian Leppin
Keyword(s):  
Finite Element ◽  
Finite Element Simulation ◽  
Plastic Material ◽  
Large Strain ◽  
Material Model ◽  
Material Behavior ◽  
Flow Rule ◽  
Forming Process ◽  
Aluminum Sheets ◽  
Element Simulation

Aluminum sheets used for beverage cans show a significant anisotropic plastic material behavior in sheet metal forming operations. In a deep drawing process of cups this anisotropy leads to a non-uniform height, i.e., an earing profile. The prediction of this earing profiles is important for the optimization of the forming process. In most cases the earing behavior cannot be predicted precisely based on phenomenological material models. In the presented work a micromechanical, texture-based model is used to simulate the first two steps (cupping and redrawing) of a can forming process. The predictions of the earing profile after each step are compared to experimental data. The mechanical modeling is done with a large strain elastic visco-plastic crystal plasticity material model with Norton type flow rule for each crystal. The response of the polycrystal is approximated by a Taylor type homogenization scheme. The simulations are carried out in the framework of the finite element method. The shape of the earing profile from the finite element simulation is compared to experimental profiles.

scholarly journals Effect of the Supports’ Positions on the Vibration Characteristics of a Flexible Rotor Shafting

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Miaomiao Li ◽  
Zhuo Li ◽  
Liangliang Ma ◽  
Rupeng Zhu ◽  
Xizhi Ma
Keyword(s):  
Finite Element ◽  
Finite Element Simulation ◽  
Vibration Characteristics ◽  
Rotor System ◽  
Experimental Investigations ◽  
Flexible Rotor ◽  
Bending Vibration ◽  
First Order ◽  
Element Simulation

In this study, we evaluated the effect of changing supports’ position on the vibration characteristics of a three-support flexible rotor shafting. This dependency was first analyzed using a finite element simulation and then backed up with experimental investigations. By computing a simplified rotor shafting model, we found that the first-order bending vibration in a forward whirl mode is the most relevant deforming mode. Hence, the effect of the supports’ positions on this vibration was intensively investigated using simulations and verified experimentally with a house-made shafting rotor system. The results demonstrated that the interaction between different supports can influence the overall vibration deformation and that the position of the support closer to the rotor has the greatest influence.

Finite Element Simulation of Vacuum Hot Bulge Forming of Titanium Alloy Cylindrical Workpiece

2011 ◽  
Vol 675-677 ◽  
pp. 921-924 ◽  
Author(s):  
Ming Wei Wang ◽  
Chun Yan Wang ◽  
Li Wen Zhang
Keyword(s):  
Numerical Simulation ◽  
Finite Element ◽  
Titanium Alloy ◽  
Finite Element Simulation ◽  
Process Parameters ◽  
Fe Model ◽  
Analysis Software ◽  
Forming Process ◽  
Element Simulation ◽  
Cylindrical Workpiece

Vacuum hot bulge forming (VHBF) is becoming an increasingly important manufacturing process for titanium alloy cylindrical workpiece in the aerospace industries. Finite element simulation is an essential tool for the specification of process parameters. In this paper, a two-dimensional nonlinear thermo-mechanical couple FE model was established. Numerical simulation of vacuum hot bulge forming of titanium alloy cylindrical workpiece was carried out using FE analysis software MSC.Marc. The effects of process parameter on vacuum hot bulge forming of BT20 titanium alloy cylindrical workpiece was analyzed by numerical simulation. The proposed an optimized vacuum hot bulge forming process parameters and die size. And the corresponding experiments were carried out. The simulated results agreed well with the experimental results.

Optimum Design of Forming Sequence of One-Piece Automobile Steel Wheels without Welding Using Finite Element Simulation

2007 ◽  
Vol 340-341 ◽  
pp. 773-778
Author(s):  
Y. Abe ◽  
J. Watanabe ◽  
Kenichiro Mori
Keyword(s):  
Finite Element ◽  
Finite Element Simulation ◽  
Optimum Design ◽  
Deep Drawing ◽  
Outer Side ◽  
Forming Process ◽  
Multi Stage ◽  
Element Simulation ◽  
Automobile Steel ◽  
The One

A forming sequence of one-piece automobile steel wheels without welding was designed. In this forming process, the one-piece wheel was formed from a circular blank only by multi-stage stamping operations, and a deeply drawn cup was formed into the wheel. Two humps of the rim flange for fixing the tire were formed in the flaring and flanging stages. The humps of the rim in the opening and outer side were formed by buckling the inner flange of the rim, and by swelling the outer flange with an upper die having a short land, respectively. In addition, the number of stages was considerably reduced from 16 stages to only 9 stages by combining the deep drawing and ironing stages and by adding a holding die in the flaring stages. The forming sequence of the one-piece wheels was evaluated by both finite element simulation and miniature experiment.

The Analysis of the Interface States of Low-Density Materials in the Forming Process

2012 ◽  
Vol 503-504 ◽  
pp. 696-699
Author(s):  
Qiao Li Wang ◽  
Yu Dong Zheng ◽  
Xin Liang ◽  
Ying Ling ◽  
Kun Qiao ◽  
...  
Keyword(s):  
Finite Element ◽  
Theoretical Analysis ◽  
Finite Element Simulation ◽  
Interface State ◽  
Interface States ◽  
Finite Element Models ◽  
Low Density ◽  
Forming Process ◽  
Element Simulation ◽  
Main Factors

The interface of two low-density materials is bent in the forming process, which decreases the performance of materials. The theoretical analysis of the interface state in the forming process was taken to solve this problem, and the results indicated that the viscosity of the low-density material was very important to the interface state. The finite element simulation was also used to investigate the factors that affect the interface state. The results revealed the viscosity of material and the pressure were the main factors that affected the interface state; the stress and displacement at the interface could be accurately predicted by the finite element models. The ultimate aim was to modify the relevant parameters in a way that could obtain the required interface states.

Sign in / Sign up

Export Citation Format

Share Document