Study of the Effect of Material Properties and Sheet Thickness on Formability of Conical Parts in Hydro-Mechanical Deep Drawing Assisted by Radial Pressure

2012 ◽  
Vol 445 ◽  
pp. 149-154 ◽  
Author(s):  
A. Hashemi ◽  
M. Mashhadi ◽  
Mohammad Bakhshi-Jooybari ◽  
A. Gorji
Keyword(s):  
Material Properties ◽  
Deep Drawing ◽  
Distribution Curve ◽  
Thickness Distribution ◽  
Pure Copper ◽  
Sheet Thickness ◽  
Radial Pressure ◽  
Thickness Reduction ◽  
Copper Sheet ◽  
St14 Steel

Conical parts have a lot of usage in industries. Therefore, it is important to form these parts with high accuracy. In sheet forming processes, producing conical parts is one of the most difficult aspects. The two major problems that occur in the production of conical parts are rupturing and wrinkling. Among the forming processes for producing conical parts, the most capable one is hydroforming deep drawing. In this study, the effects of material properties and initial sheet thickness on forming and thickness reduction of the part were examined by using hydro-mechanical deep drawing assisted by radial pressure. For investigating these two parameters, pure copper and st14 steel are used. In experimental evaluation, sheets with thicknesses of 2.5 mm were used. In the simulation study, the thicknesses of 0.5, 1, and 2 mm were also examined. There is a good agreement between experimental and simulation findings. The results showed that for thinner sheets, the thickness reduction is less, and thus, a more uniform thickness distribution curve was obtained. Also, it was illustrated that for St14 steel sheet the thickness distribution curve will be more uniform compared with that of pure copper sheet.

Effect of Punch Profile on Thickness Distribution in Hydromechanical Deep Drawing of Conical-Cylindrical Parts

2012 ◽  
Vol 445 ◽  
pp. 143-148 ◽  
Author(s):  
M. Mashhadi ◽  
A. Hashemi ◽  
Mohammad Bakhshi-Jooybari ◽  
A. Gorji
Keyword(s):  
Transition Zone ◽  
Deep Drawing ◽  
Thickness Distribution ◽  
Sheet Material ◽  
Radial Pressure ◽  
Simulation Software ◽  
Geometrical Parameters ◽  
Minimum Thickness ◽  
Cylindrical Parts ◽  
St14 Steel

Hydro-mechanical deep drawing assisted with radial pressure (HDDRP) is used in industry to produce complex parts from sheet metals. This process is affected by parameters such as : pressure path, geometrical parameters of punch and die, friction between punch and sheet, etc. Investigating these parameters to acquire optimal parameters to produce the desired part is essential. In this study, the effects of the radius of punch tip and the radius of the transition zone from conical to cylindrical geometry, on forming and thickness distribution of parts have been studied. In performing the investigation, a specific geometry was considered for punch and different radiuses for punch tip and the transition zone were selected. The type of the sheet material examined is St14 steel. First, the process was simulated by the finite element simulation software, ABAQUS 6.9, and then some experiments were done to check the accuracy of the simulations. There is an acceptable conformity between the results. The results showed that the radius of punch tip is more effective than that of the transition zone, so with increasing the radius of punch tip, the minimum thickness increases and thickness distribution becomes more uniform.

scholarly journals Effect of Tool Geometry Parameters on the Formability of a Camera Cover in the Deep Drawing Process

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3993
Author(s):  
Thanh Trung Do ◽  
Pham Son Minh ◽  
Nhan Le
Keyword(s):  
Deep Drawing ◽  
Thickness Distribution ◽  
Metal Flow ◽  
Sheet Thickness ◽  
Side Wall ◽  
Tool Geometry ◽  
Drawing Process ◽  
Nose Radius ◽  
Deep Drawing Process

The formability of the drawn part in the deep drawing process depends not only on the material properties, but also on the equipment used, metal flow control and tool parameters. The most common defects can be the thickening, stretching and splitting. However, the optimization of tools including the die and punch parameters leads to a reduction of the defects and improves the quality of the products. In this paper, the formability of the camera cover by aluminum alloy A1050 in the deep drawing process was examined relating to the tool geometry parameters based on numerical and experimental analyses. The results showed that the thickness was the smallest and the stress was the highest at one of the bottom corners where the biaxial stretching was the predominant mode of deformation. The problems of the thickening at the flange area, the stretching at the side wall and the splitting at the bottom corners could be prevented when the tool parameters were optimized that related to the thickness and stress. It was clear that the optimal thickness distribution of the camera cover was obtained by the design of tools with the best values—with the die edge radius 10 times, the pocket radius on the bottom of the die 5 times, and the punch nose radius 2.5 times the sheet thickness. Additionally, the quality of the camera cover was improved with a maximum thinning of 25% experimentally, and it was within the suggested maximum allowable thickness reduction of 45% for various industrial applications after optimizing the tool geometry parameters in the deep drawing process.

Thickness Distribution in Conical Parts Formed by Hydroforming and Conventional Multistage Deep Drawing Processes

2011 ◽  
Vol 189-193 ◽  
pp. 2884-2887
Author(s):  
Abdolhamid Gorji ◽  
Amir Reza Yaghoubi ◽  
Mohammad Bakhshi-Jooybari ◽  
Salman Norouzi
Keyword(s):  
Deep Drawing ◽  
Metal Forming ◽  
Thickness Distribution ◽  
Pure Copper ◽  
Experimental Program ◽  
Drawing Process ◽  
Blank Holder ◽  
Sheet Surface ◽  
Two Stages ◽  
Explosive Forming

Forming conical parts is one of the difficult fields in sheet metal forming processes. Because of low contact area of the sheet with the punch in the initial stages of forming, too much tension applied to the sheet that it causes bursting. Furthermore, since the major part of the sheet surface between the blank holder and punch tip is free, wrinkles appears on the wall of the drawn parts. These parts are normally formed in industry by processes such as spinning, explosive forming or multistage deep drawing. Hydroforming deep drawing is one of the special deep drawing processes which have been introduced in order to overcome some inherent problems in the conventional deep drawing with rigid tools. In the present work, an experimental program has been carried out to form and compare the forming pure copper conical-cylindrical cups by hydroforming and conventional multistage deep drawing processes. The conical parts in conventional deep drawing process formed in two stages. The results of the study demonstrate that thickness distribution are more uniform in the parts formed by hydroforming compared to conventional multi stages deep drawing processes.

scholarly journals Investigation of Thickness Distribution Variation in Deep Drawing of Conical Steel Products

2021 ◽  
Vol 39 (4A) ◽  
pp. 586-598
Author(s):  
Muhsin J. Jweeg ◽  
Adnan I. Mohammed ◽  
Mohammed S. Jabbar
Keyword(s):  
Sheet Metal ◽  
Deep Drawing ◽  
Thickness Distribution ◽  
Sheet Thickness ◽  
Galvanized Steel ◽  
Thickness Variation ◽  
Low Carbon ◽  
Nose Radius ◽  
Numerical Work ◽  
Punch Velocity

This study investigates the thickness variation behavior of deep drawing conical products under the effect of different forming parameters such as die wall inclination angle, punch velocity, sheet thickness, and sheet metal type. Two types of sheet metal were used, low carbon (AISI 1008) and galvanized steel sheets, of 110 mm diameters circular blanks at 0.9 and 1.2mm thickness formed by tooling set (punch, die, and blank holder). The conical dies inclination angles were at 70ᵒ, 72ᵒ, and 74ᵒ where, the punch velocity was 100, 150, and 200 mm/min. Numerical simulation was conducted using ABAQUS 6.14 where a dynamic explicit solver was used to perform forming of conical products. The results show that maximum thinning occurs at punch nose radius region and maximum thickening in sidewall region and thinning are increased with the increasing of die sidewall angle and sheet thickness. In regard to sheet type, the Lankford coefficients r-value shows a great role in thinning behavior with respect to rolling (r-values direction). The results have shown a good agreement between experimental and numerical work with a maximum discrepancy of 5%.

scholarly journals Effects of Variable Punch Speed and Blank Holder Force in Warm Superplastic Deep Drawing Process

Metals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 493
Author(s):  
Ken-ichi Manabe ◽  
Kentaro Soeda ◽  
Akinori Shibata
Keyword(s):  
Wall Thickness ◽  
Deep Drawing ◽  
Elementary Theory ◽  
Large Strain ◽  
Thickness Distribution ◽  
Sheet Thickness ◽  
Drawing Ratio ◽  
Superplastic Material ◽  
Wall Thickness Distribution ◽  
Punch Speed

A cylindrical deep drawing test was conducted for the purpose of improving the drawability, product accuracy, and quality in warm deep drawing using a superplastic material with large strain rate dependence. Then, the effects of blank holding force (BHF) and punch speed (SPD) on the flange wrinkle behavior and wall thickness distribution were investigated by experiments and theoretical analysis. A Zn-22Al-0.5Cu-0.01Mg alloy superplastic material SPZ2 with a sheet thickness of 1 mm was employed as the experimental material, and a cylindrical deep drawing experiment with the drawing ratio (DR) of 3.1 and 5 was performed at 250 °C. A good agreement was qualitatively obtained between the elementary theory on the flange wrinkle limit, the fracture limit, and the experimental results. In addition, the authors examined each variable BHF and SPD method obtained from the theory and experimentally demonstrated that the variable BHF method has a great effect on uniform wall thickness distribution and that variable SPD has a great effect on shortening the processing time for superplastic materials. Furthermore, the authors demonstrated the effectiveness of the variable BHF/SPD deep drawing method that varies both BHF and SPD simultaneously.

The Effect of Process Parameters on Thickness Distribution in Hydroforming of Conical-Cylindrical Cups

2011 ◽  
Vol 473 ◽  
pp. 176-181
Author(s):  
Abdolhamid Gorji ◽  
Mohammad Bakhshi-Jooybari ◽  
Salman Norouzi ◽  
S.J. Hosseinipour ◽  
G. Mohammad-Alinejad
Keyword(s):  
Deep Drawing ◽  
Thickness Distribution ◽  
Pure Copper ◽  
Cone Angle ◽  
Cylindrical Part ◽  
Drawing Ratio ◽  
Simulation And Experiment ◽  
Thickness Variations ◽  
Tip Radius ◽  
Explosive Forming

Forming conical parts is one of the complex and difficult fields in sheet metal forming processes. These parts are normally formed in industry by spinning, explosive forming or multistage deep drawing processes. In this paper, forming pure copper conical–cylindrical cups in the hydrodynamic deep drawing process was studied using finite element (FE) simulation and experiment. In this study, the effect of cone angle and punch tip radius on bursting and thickness distribution of the parts and also the effect of pressure path on thickness distribution were examined. Using the measurements of strains and thickness variations on the cup wall, the quality of the drawn cups was evaluated. The results demonstrated that increasing cone angle will lead to higher drawing ratio and uniform thickness distribution. Also, it was concluded that in the conical-cylindrical part the punch tip radius region is the most critical zone. At this zone, the more the cone angle the less the possibility of tearing is. In addition, with increasing punch tip radius it could be seen that the thickness reduction decreases.

Effect of Tool Shape on Increases in Sheet Thickness during Drawing and Ironing

2011 ◽  
Vol 320 ◽  
pp. 462-467 ◽  
Author(s):  
Yuji Kotani ◽  
Akihiro Watanabe ◽  
Hisaki Watari
Keyword(s):  
Sheet Metal ◽  
Deep Drawing ◽  
Thickness Distribution ◽  
Sheet Thickness ◽  
Original Material ◽  
Large Area ◽  
Forming Simulation ◽  
Manufacturing Method ◽  
Metal Thickness ◽  
Tool Shape

Prior knowledge of local increase in sheet metal thickness due to forming of products would contribute to decreasing total product weight by giving the product designer an advance notice of the appropriate sheet metal thickness distribution in a product. A method using simulation to accurately predict such increases would greatly aid the designer in this task. The designer can then distribute thicker parts where a large area moment of inertia is needed from the viewpoint of structural strength in a given section. In terms of optical designing for variable thickness distribution in products, the sheet thickness in a product need not be considered constant. This paper presents the forming prediction during deep drawing. To clarify the mechanism of increase in sheet thickness, a 3-D forming simulation is performed during deep drawing by using the finite element method (FEM). The effects of tool shapes—angle of contact with the original material and the contacting length of the punch with the material—that mainly affect the change in thickness of the original material are investigated. The thickness distribution of drawn cups is measured for comparing the simulation results obtained by FEM with the experimental results. It is shown that controlling the distribution of sheet metal thickness is possible if the original material is relatively thick, and when an appropriate manufacturing method is selected.

Effect of process parameters on micro flexible deep drawing of stainless steel 304 cups utilizing floating ring: Simulation and experiments

2020 ◽  
Vol 235 (1-2) ◽  
pp. 134-143
Author(s):  
Ihsan Irthiea ◽  
Zaid Mahmood
Keyword(s):  
Deep Drawing ◽  
Thickness Distribution ◽  
High Surface ◽  
Sheet Thickness ◽  
Simulation Models ◽  
Drawing Ratio ◽  
High Surface Quality ◽  
Micro Deep Drawing ◽  
Stainless Steel 304 ◽  
Flexible Die

Due to its simplicity, versatility of process and feasibility of prototyping, using flexible tools in sheet forming seems appropriate for producing cups at microscales. This article presents a novel micro deep drawing technique in which a cooperation of a floating ring, as a primary rigid die, with a rubber pad, as a main flexible die, is employed for forming micro-cups. The function of the floating ring is to overcome minor wrinkles that commonly occur at flange portion, while the flexible die is to complete the forming stroke. The influence of initial sheet thickness, drawing ratio, punch corner radius and rubber height is studied through simulations and experiments. Furthermore, three size scales are adopted to investigate the possibility of using the proposed technique under different process dimensions. The code ABAQUS/Standard is utilized to build the finite element models and thereafter micro-forming experiments are carried out to verify the numerical results. For this purpose, a special setup is developed to be compatible with simulation models. The results show that the formed cups are characterized by very accurate dimensions, high surface quality, homogeneous wall thickness distribution in terms of maximum thinning and thickening and relatively large aspect ratio.

scholarly journals Investigation of a Modified Hydrodynamic Deep Drawing Assisted by Radial Pressure with Inward Flowing Liquid Process

2018 ◽  
Vol 190 ◽  
pp. 09003
Author(s):  
Maziar Khademi ◽  
Milad Sadegh yazdi ◽  
Mohammad Bakhshi-Jooybari ◽  
Hamid Gorji
Keyword(s):  
Deep Drawing ◽  
Thickness Distribution ◽  
Radial Pressure ◽  
Drawing Ratio ◽  
Cavity Pressure ◽  
Flowing Liquid ◽  
Hydrodynamic Deep Drawing ◽  
Simultaneous Control ◽  
Die Set ◽  
Cylindrical Parts

Hydrodynamic Deep Drawing (HDDRP), the combination of hydroforming and conventional deep drawing, accommodates the advantages of the two processes. A technique, called HDDRP with inward flowing liquid, has been introduced based on the idea of insertion of radial pressure around the blank rim. The radial pressure created on the blank edge, can increase the drawing ratio. Thus, increasing the radial pressure to an amount greater than the cavity pressure, and independent control of these pressures is the basic idea of this research for forming cylindrical parts. To perform the experiments, two independent pumps were used to provide the two pressures independently. The pressure supply system and the die set were designed in a way that provides simultaneous control of the pressures throughout the process. Then, the effects of radial pressure paths on thickness distribution of cylindrical St13 cups were investigated. In addition, a comparison between HDDRP and HDDRP with inward flowing liquid processes has been performed experimentally. Results indicated that using a higher radial pressure than the cavity pressure and controlling their values at any moment of the process enhances the thickness distribution of the formed part in all regions.

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