Evaluation of Forming Methods for the Pre-shaping of Miura-Structures Made of Sheet Metal Materials

2021 ◽  
pp. 75-84
Author(s):  
M. Görz ◽  
M. Liewald ◽  
K. R. Riedmüller
Keyword(s):  
Sheet Metal ◽  
Metal Materials ◽  
Forming Methods

scholarly journals TENDENCIES IN FORMING SHEET METAL PARTS USING INCREMENTAL FORMING ADVANCED TECHNOLOGIES

2019 ◽  
Vol 25 (3) ◽  
Author(s):  
CATALINA CIOFU ◽  
BOGDAN CHIRITA ◽  
ROXANA LUPU ◽  
COSMIN GRIGORAS ◽  
CRINA RADU ◽  
...  
Keyword(s):  
Sheet Metal ◽  
Incremental Forming ◽  
Stretch Forming ◽  
Micro Forming ◽  
Forming Process ◽  
Metal Parts ◽  
Sheet Metal Parts ◽  
Advanced Technologies ◽  
Metal Materials ◽  
Forming Methods

Stretch forming of sheet metal materials is a highly required process in aerospace industry for manufacturing skin parts. Automation of some processes such as cutting, punching, forming, shearing and nesting in conventional manufacturing tends to combine these forming methods. Some researches are made on the formability of sheet metal materials obtained in incremental forming process with stretch forming and water jet incremental micro-forming with supporting dies. This paper is an attempt to review the newly researches made on optimization of manufacturing metal skin parts to achieve geometrical accuracy.

scholarly journals TENDENCIES IN FORMING SHEET METAL PARTS USING INCREMENTAL FORMING ADVANCED TECHNOLOGIES

2019 ◽  
Vol 25 (3) ◽  
pp. 15-21
Author(s):  
CATALINA CIOFU ◽  
BOGDAN CHIRITA ◽  
ROXANA LUPU ◽  
COSMIN GRIGORAS ◽  
CRINA RADU ◽  
...  
Keyword(s):  
Sheet Metal ◽  
Incremental Forming ◽  
Stretch Forming ◽  
Micro Forming ◽  
Forming Process ◽  
Metal Parts ◽  
Sheet Metal Parts ◽  
Advanced Technologies ◽  
Metal Materials ◽  
Forming Methods

Stretch forming of sheet metal materials is a highly required process in aerospace industry for manufacturing skin parts. Automation of some processes such as cutting, punching, forming, shearing and nesting in conventional manufacturing tends to combine these forming methods. Some researches are made on the formability of sheet metal materials obtained in incremental forming process with stretch forming and water jet incremental micro-forming with supporting dies. This paper is an attempt to review the newly researches made on optimization of manufacturing metal skin parts to achieve geometrical accuracy.

On the thinning variations in hydrostatic forming of sheet metal

2021 ◽  
Vol 15 (1) ◽  
pp. 7824-7836
Author(s):  
Thu Thi Nguyen ◽  
N.D. Trung
Keyword(s):  
Sheet Metal ◽  
Thickness Distribution ◽  
Input Parameter ◽  
Relative Depth ◽  
Technological Parameters ◽  
Forming Technology ◽  
Input Parameters ◽  
Forming Characteristics ◽  
Cylindrical Cup ◽  
Forming Methods

In sheet metal forming, thinning phenomenon is one of the most concerned topics to ameliorate the final quality of the manufactured parts. The thinning variations depend on many input parameters, such as technological parameters, geometric shape of die, workpiece’s materials, and forming methods. Hydrostatic forming technology is particularly suitable for forming thin-shell products with complex shapes. However, due to the forming characteristics, the thinning variations in this technology are much more intense than in other forming methods. Therefore, in this paper, an empirical study is developed to determine the thinning variations in hydrostatic forming for cylindrical cup. Measurement of thickness at various locations of deformed products are conducted to investigate the thickness distribution and determine the dependence of the largest thinning ratio on the input parameters (including the blank holder pressure, the relative depth of the die and the relative thickness of the workpiece). The results are expressed in charts and equation which allow determining the effect of each input parameter on the largest thinning ratio.

Today's sheet metal materials and their forming properties

2004 ◽  
Vol 35 (7) ◽  
pp. 423-430 ◽  
Author(s):  
F.-W. Bach ◽  
A. Roßberg ◽  
M. Schäperkötter ◽  
M. Schaper ◽  
L. Walden ◽  
...  
Keyword(s):  
Sheet Metal ◽  
Metal Materials

scholarly journals Concept development of a method for identifying friction coefficients for the numerical simulation of clinching processes

2021 ◽  
Author(s):  
Max Böhnke ◽  
Moritz Rossel ◽  
Christian R. Bielak ◽  
Mathias Bobbert ◽  
Gerson Meschut
Keyword(s):  
Numerical Simulation ◽  
Sheet Metal ◽  
Test Method ◽  
Image Correlation ◽  
Pollutant Emissions ◽  
Friction Coefficients ◽  
Frictional Behavior ◽  
Metal Material ◽  
Metal Materials ◽  
Interface Pressures

AbstractIn order to reduce fuel consumption and thus pollutant emissions, the automotive industry is increasingly developing lightweight construction concepts that are accompanied by an increasing usage of aluminum materials. Due to poor weldability of aluminum in combination with other materials, mechanical joining methods such as clinching were developed and established in series production. In order to predict the relevant characteristics of clinched joints and to ensure the reliability of the process, it is simulated numerically during product development processes. In this regard, the predictive accuracy of the simulated process highly depends on the implemented friction model. In particular, the frictional behavior between the sheet metals as well as between the sheet metal and clinching tools has a significant impact on the geometrical formation of the clinched joint. No testing methods exist that can sufficiently investigate the frictional behavior in sheet materials, especially under high interface pressures, different relative velocities, and long friction paths, while allowing a decoupled consideration of the test parameters. This paper describes the development of further testing concepts based on a proven tribo-torsion test method for determining friction coefficients between sheet metal materials for the simulation of clinching processes. For this purpose, the correlation of interface pressure and the relative velocity between aluminum and steel sheet material in clinching processes is investigated using numerical simulation. Based on these findings, the developed concepts focus on determining friction coefficients at interface pressures of the above materials, yield stress, as well as the reproduction of the occurring friction conditions between sheet metal materials and tool surfaces in clinching processes using tool substitutes. Furthermore, wear investigations between sheet metal material and tool surface were carried out in the friction tests with subsequent EDX analyses of the frictioned tool surfaces. The developed method also allows an optical deformation measurement of the sheet metal material specimen by means of digital image correlation (DIC). Based on a methodological approach, the test setups and the test systems used are explained, and the functionality of the concepts is proven by experimental tests using different sheet metal materials.

Improving the Cut Edge by Counter-Shaving

2007 ◽  
Vol 344 ◽  
pp. 217-224 ◽  
Author(s):  
Hartmut Hoffmann ◽  
Florian Hörmann
Keyword(s):  
Sheet Metal ◽  
Research Work ◽  
Dimensional Accuracy ◽  
Burr Formation ◽  
Cut Edge ◽  
Edge Quality ◽  
Metal Materials ◽  
The Right ◽  
Two Stages

In blanking operations the cut edge of the sheet metal is not clear due to fracturing and burr formation by the shearing process. For precision parts with high quality and dimensional accuracy, often secondary machining is necessary. Shaving, in particular, counter-shaving, is a shearing operation to improve the cut edge quality of a blanked part or punched hole in two stages. This paper introduces a progressive die tool to realize the counter-shaving process on a single acting press. In order to realize the shaving operation in the opposite punching direction, the punch needs to move in counter direction. The burr and fracture zone left on the sheet metal after the first stage will be removed by the counter-shaving operation. By choosing the right process parameter a sharpedge transition is formed, without any rollover, between the upper surface of the sheet metal and the sheared-edge. Different punch geometries as well as the corresponding process parameters were part of the research work in order to improve the cut edge. Experimental and FEM results are presented for two sheet metal materials at three thicknesses.

A review of conventional and modern single-point sheet metal forming methods

2003 ◽  
Vol 217 (2) ◽  
pp. 213-225 ◽  
Author(s):  
E Hagan ◽  
J Jeswiet
Keyword(s):  
Sheet Metal ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
Single Point ◽  
Small Region ◽  
Numerical Control ◽  
Localized Deformation ◽  
Flow Forming ◽  
Conventional Spinning ◽  
Forming Methods

The use of computers in manufacturing has enabled the development of several new metal forming processes that are based upon older technologies. In this case modifications have been made to traditional forming methods such as conventional spinning and shear forming. These two processes are similar in that the deformation mechanism is localized to a small region under the forming tool. Recent advances in computing power have enabled this localized deformation to be accurately controlled and studied. Spinning, shear forming and flow forming are limited to forming parts that are symmetrical about the revolving lathe axis. Current research has been focused on forming non-symmetrical parts using computer numerical control (CNC) technology, without the need for costly dies. A comparison of traditional and modern forming methods is presented here in an attempt to illustrate the evolution of different incremental sheet metal forming techniques. Emphasis is placed on conventional spinning, shear forming and modern computer-controlled forming methods that are currently being studied.

Improvement of Sheet Metal Properties by Inducing Residual Stresses into Sheet Metal Components by Embossing and Reforming

2021 ◽  
Author(s):  
Stefan Walzer ◽  
Mathias Liewald ◽  
Nicola Simon ◽  
Jens Gibmeier ◽  
Hannes Erdle ◽  
...  
Keyword(s):  
Residual Stresses ◽  
Sheet Metal ◽  
Local Property ◽  
Experimental Investigations ◽  
Forming Process ◽  
Novel Approach ◽  
Forming Strategy ◽  
Metal Materials ◽  
Metal Properties ◽  
The One

In sheet metal forming, combination of embossing and reforming allows the mechanical properties of sheet metal materials to be specifically improved. Here, local property modification is achieved by the residual stresses induced as a result of the one-sided embossing process followed by a reforming step. The residual stresses induced in this specific way can lead to a significantly increase in the fatigue strength of processed sheet metal components. However, in order to ensure this kind of component optimization in continuous operation, the induced stresses have to be homogeneous. In this respect, the main objective of the study reported about in this paper was to identify a forming strategy, consisting of the process steps embossing and reforming, that generates preferably homogeneous residual stress distributions into sheet metal blanks. For this, numerical and experimental investigations were carried out with samples of the stainless steel (X6Cr17) having a thickness of 1.5 mm. It was found that embossing and reforming, integrated into a conventional forming process, is a novel approach to specifically induce very localized homogeneous compressive residual stresses in sheet metal materials. This eliminates the need for costly post-processing by means of surface treatment.

Sign in / Sign up

Export Citation Format

Share Document