Simulation of Fricton Ratios at Deep-Drawing Process

Advances in Mechanical Engineering

The paper investigated the effect of localized friction on sheet thinning under lubricated conditions in the deep-drawing process. The Finite Element Analysis (FEA) was used to evaluate the sheet thinning of the AISI 304 sheet under six segmented blank-sheet interfaces. Different values of variable coefficient of friction (VCOF) in each segmented area were investigated, and the sheet thickness values at the considered areas were measured. The regression analysis models (Linear Regression, Response Surface Method, and Polynomial Regression) was used to determine the relationships between VCOF and sheet thinning. The results showed that the Linear Regression showed the best fit. The significant factor analysis was also carried out to determine how the localized friction affected the sheet thinning. The contributions of VCOF from at least two segmented areas affected the sheet thinning at any particular location. The obtained relationships of the VCOF and sheet thinning could be benefi...

— Deep drawing is a sheet metal forming process in which a sheet metal blank is radially drawn into a forming die by the mechanical action of a punch. Deep drawing process is a shape transforming method. Defects like cracks and wrinkling of deep drawing occur very often in conventional cylindrical deep drawing process because of the lower forming ability of aluminum alloy sheet at room temperature. Therefore, a different approach is discussed in my research to obtain some new prediction of behavior with variations of deep drawing. This method helps to push the sheet metal in different angular direction. In addition, the effect of coefficient of friction is predicted while performing deep drawing. In order to avoid the costly, tedious and difficult experiments, modern manufacturing industry is based on the analysis of forming processes in numeral atmosphere before the actual production setup. In the work, the single stage deep drawing process is used by means of a finite element analysis. Simulation of the deep drawing process for determining stress distribution in the drawn component for different variations is explained in my work. The distribution of stress in the drawn component is obtained. Thus simulation of deep drawing is being carried out on alloy steel at different die angles and to check its performance. Also its behavior is tested at various coefficient of friction. The result of simulation will be beneficial to the tool designer and the manufacturing industries doing work in this field.

2011

Deep-drawing processes are usually used in automotive industry. In this area the specimen dimensions are between same millimetres in case of small devices to metres in case of a car body. In this study it is presented a comparative analysis about the influence of the punch geometry on the deep-drawing force. Experimental deep-drawing tests were performed. The material used in experiments was steel sheets with 0.5 mm in thickness. In the experiments were used four different dies with different geometries. The influence of the die radius on the deep drawing force was studied. From the experimental data it was concluded that the punch geometry have the main influence on the deep-drawing force. The small differences seen in the case of using dies with small radius lead to the conclusions that this parameter have no significant influence on the deep-drawing force.

2019

Friction between the interface workpiece and tooling has considerable importance in sheet metal forming operations; an accurate description of the friction is necessary to analyze and design new workpieces and tooling. This work suggests a methodology to determine and evaluate the mean coefficient of friction (COF) using the Finite Element Method (FEM) through Dynaform for the aluminum alloy AA1100. The results indicate that this methodology is consistent with reality. It is also observed that the software tends to diverge from the measured results because the software considers the COF to be constant along the process. Despite this trend, the greatest distance between the maximum drawing force given by the measurement and the numeric simulation was not high: it was approximately 6%. Workpiece strain measurements were collected to compare with the numerical simulation results, and it was observed that they are generally in agreement.

SSRG International Journal of Mechanical Engineering, 2024

Deep drawing is used widely to manufacture objects out of sheet metal. Several geometric parameters can generate deep drawing products that are free of defects. The radius of the Punch corner, Clearance and radius of the die corner are the three parameters that have the biggest effects on deep drawing. The stress distribution of an SS 316 cylindrical cup was examined in this study while considering these parameters. The finite element simulation of this process is performed in ABAQUS software. FEM simulation using the isotropic hardening law was carried out. Response surface methodology is used to design experiments. When the outcomes of the FEA and the experiments were compared, they agreed well. The most influential parameters were identified by ANOVA analysis. The finding showed that the optimum parameter of the punch corner radius (PCR) should be 5.3 mm, the Die Corner Radius (DCR) should be 6.6 mm, and clearance should be 1.07 mm to minimize stress distribution.

Arabian Journal for Science and Engineering, 2017

Carrying out various experiments organized based on the design of experiments method, the deep drawing process is investigated entirely in this paper. The influences of eight main process parameters including punch and die radii, blank thickness, punch velocity, lubrication conditions at the interfaces of blank-die, blank-punch, and blank-blank holder as well as the blank holder force on the process outputs comprising punch force and sheet thickness variation are investigated. The analysis of variance method is considered to define the procedure by which these eight parameters be adjusted for deep drawing process to minimize the punch force and maximize the uniform thickness distribution in the products. It was found that for punch force, in addition to blank thickness, die and punch radii as well as the BHF are, respectively, the main essential parameters. Besides, blank thickness, die radius, and lubrication condition at the holder-blank interface are the most effective parameters on thickness distribution. Accordingly, initial blank thickness and die shoulder radius could be taken into account as two important parameters in deep drawing process should be set up appropriately to accomplish the minimum punch force and uniform thickness distribution together.

Materials Today: Proceedings, 2017

In this paper FEA simulations are carried out for axis-symmetric deep drawing of usibore 1500 boron steel to examine effect of friction coefficient on the product quality. Usibore 1500 steel has extensively been used in manufacturing automobile body parts. Mechanical properties of usibore 1500 steel have been taken from published literature. Thickness distribution, VonMises stress and FLD curves have been studied for analysing the effect of friction. Thickness variation is one of the easy ways to check the quality of product. The results show that as coefficient of friction coefficient lowers, thickness distribution and quality of product improve. Moreover Von-Mises stresses also get reduced at lower friction. Also improved FLD curve obtained at lower friction value that indicates formability improvement.

The main objective of this paper is to find the most effective parameters in deep drawing process to produce a cup of required shape and size. Limit Drawing Ratio is one of the parameters that indicate the drawability of material. It is defined as the ratio of blank diameter to punch diameter at the onset of tearing. Deep drawing products in modern industries usually have a complicated shape, so these have to undergo several successive operations to obtain a final desired shape. In this work the effect of various parameters like die and punch corner radii, clearance, friction coefficient between die and punch, punch diameter on limit drawing ratio is investigated and presented by using an explicit finite element code LS-DYNA 3D.

Materials

Friction is one of the most important technological phenomena and has a large influence on the flow characteristics of a deformed material. A strip drawing friction test was used to evaluate the friction characteristics of 0.8 mm thick DC04 steel sheets in a sheet forming operation. Friction tests were carried out using a specially designed friction simulator and uniaxial tensile tests were carried out to determine the mechanical properties of the specimens. In addition, measurements of the sheet surface topography were carried out to identify the tribological properties of the specimens. The friction tests were conducted under different pressure and lubrication conditions. A comparative analysis of the results of the friction tests revealed different changes in the surface topography of the test sheets which can be associated with specific friction mechanisms. It was found that the effectiveness of lubrication depends on the lubricant viscosity and nominal pressure. Increasing the ...

Le Journal de Physique IV, 1993

The mathematical modelling of sheet metal forming operation is extended to include information about the particular tool and the particular machine that will be used in the "real" process. Particular attention is paid to the structure and to the operation of a mechanical press. For this type of process some control factors (parameters that the engineer can set during the fine tuning of the forming process on the machine) and some noise factors (parameters that are not under the control of the engineer) are individuated and a procedure to obtain a "robust" design of the process itself (i.e. a process optimized from the point of view of its low sensibility to the noise factors that are responsible of the loss of quality of the product) is outlined. The procedure is applied to the case of the deep drawing of an automotive rear fender, by the use of the OPTRIS finite element code, in order to demonstrate its capability .