Hydrodynamic deep drawing process assisted by radial pressure with inward flowing liquid

In the deep drawing process, achieving a higher drawing ratio has always been considered by researchers. In this study, a new concept of hydrodynamic deep drawing with two consecutive stages without additional operations such as annealing is proposed to increase the limit drawing ratio of the cups. The effective parameters were investigated numerically and experimentally in the forming of Al1200 cylindrical cups. At first, the desired value of punch diameter ratio was determined based on finite element simulation results and was utilized to increase the cup formability. Next, the effects of pressure paths on the cup thickness, separation, and rupture were studied in each forming stage. The cup formability was investigated based on a new proposed framework to obtain the maximum possible limiting drawing ratio, and the desired conditions were determined. Finally, a cup was formed with a high drawing ratio of 3.4 which was a good achievement in comparison with the literature.

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

MATEC Web of Conferences ◽

10.1051/matecconf/201819009003 ◽

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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Effect of pre-forming and pressure path on deformation behavior in multi-pass hydrodynamic deep drawing process

International Journal of Mechanical Sciences ◽

10.1016/j.ijmecsci.2017.01.010 ◽

2017 ◽

Vol 121 ◽

pp. 171-180 ◽

Cited By ~ 8

Author(s):

W.D. Li ◽

B. Meng ◽

C. Wang ◽

M. Wan ◽

L. Xu

Keyword(s):

Deep Drawing ◽

Deformation Behavior ◽

Drawing Process ◽

Deep Drawing Process ◽

Hydrodynamic Deep Drawing

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Investigation of Forming Cylindrical Parts in a Modified Hydrodynamic Deep Drawing Assisted by Radial Pressure With Inward Flowing Liquid

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4038512 ◽

2017 ◽

Vol 140 (3) ◽

Cited By ~ 4

Author(s):

Milad Sadegh Yazdi ◽

Mohammad Bakhshi-Jooybari ◽

Hamid Gorji ◽

Mohsen Shakeri ◽

Maziar Khademi

Keyword(s):

Deep Drawing ◽

Thickness Distribution ◽

Radial Pressure ◽

Chamber Pressure ◽

Drawing Ratio ◽

Forming Force ◽

Flowing Liquid ◽

Hydrodynamic Deep Drawing ◽

Study Results ◽

Formed Part

Among the sheet hydroforming processes, hydrodynamic deep drawing (HDD) process has been used to form complex shapes and can produce parts with high drawing ratio. Studies showed that radial pressure created on the edge of the sheet can decrease the drawing force and increase drawing ratio. Thus, increasing of radial pressure to an amount greater than chamber pressure, and independent control of these pressures, is the basic idea in this study. In this research, the effect of radial and chamber pressures on formability of St13 and pure copper sheets in the process of hydrodynamic deep drawing assisted by radial pressure (HDDRP) with inward flowing liquid is investigated. Giving that a significant portion of the maximum thinning of the formed part occurs in the beginning of the process, the pressure supply system used in the experimental tests was designed in a way, which provides simultaneous control of the radial and chamber pressures throughout the process. Thickness distribution, forming force, and tensile stresses are the parameters that were evaluated in this study. Results indicated that using a higher radial pressure than the chamber pressure and controlling their values in the initial stages of the process enhances the thickness distribution of the formed part in all regions. A comparison between the thickness distribution and maximum forming force of the formed parts by the HDDRP and HDDRP with inward flowing liquid methods showed that by applying the later method, parts with more uniform thickness distribution and less maximum thinning and forming force can be achieved.

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