Numerical Investigation of Tool Parameters Influence on the Interlock Forming During Flat Clinching Process

Tool parameters play a vital role in the mechanical interlock formation during the flat clinching process, to understand the influence of tool parameters on the interlock formation, the finite element software DEFORM-2D was used to build the numerical model of the flat clinching process, and the numerical model was verified by the experiment. The influences of the punch radius, punch fillet radius, and blank holder radius on the interlock formation of the clinched joint were investigated using the numerical model. Then, the relationship between the punch radius and blank holder radius was studied. The results showed that the interlock gradually increases with the increase of the blank holder radius, after that, the interlock begins to decrease. To maximize the interlock, the punch radius and the blank holder radius should be increased simultaneously. It can be concluded that the blank holder radius and the punch radius should keep in a linear relationship when designing the geometric dimensions of the flat clinch tools, which can promote the application of flat clinching process in car body manufacturing.

Springback Prediction of 7075 Aluminum Alloy V-shaped Parts in Cold and Hot Stamping

In this paper, the springback behavior of high strength aluminum alloy 7075 is studied by experiments and finite element (FE) simulation. Firstly, an analytical model is established to predict the springback angles and analyze the springback trend. The springback experimental tests are conducted by using the V-shaped stamping dies. The influence of deformation temperature, punch radius and blank holder force on the springback angles are studied. Finally, An FE simulation model is performed to investigate the deformation characteristics and springback process of the aluminum alloy sheet. The results show that the change of springback angles is direct proportional to the punch radius. The springback angles increase with the decreasing deformation temperature and the increasing blank holder force. The stress relaxation that occurs during the die holding stage is the primary reason of reducing the springback compared with cold stamping. Low blank holder force will cause side wall curl, which results in the deviation of forming size. The FE simulation model considering stress relaxation is capable of precisely predicting the change of springback angles, and the simulation results exhibit good consistency with the experimental results.

Experimental, Statistical, and Analytical Evaluation of The Springback Behavior of Martensitic 1400 Sheet in V-Bending

Ultra-high-strength Martensitic 1400 steel is preferred in the automotive industry because of its high strength as well as its light weight. In this study, Martensitic 1400 steel was subjected to the V-bending process. As a result of 48 different tests, the amount of springback resulting from the V-bending process was determined. A finite element (FE) model was then created based on these experimental data. After it was determined that the experimental results concurred with the FE model, without performing new experiments, further analyses were carried out at different temperatures. Using the results of a total of 96 FE analyses, variance analysis was performed and the effects of the operation parameters on springback were determined. As a result of the study, it was concluded that the most effective parameter on springback in the V-bending process was the die angle and that holding time had no significant effect. It was observed that the springback increased in parallel with the punch radius and die angle and that increases in temperature reduced the springback.

Hydraulic Sheet Metal Bending System

Due to increasing Globalization it is very much essential for manufacturers to produce goods having highest reliability and in required time. This is achieved by using various manufacturing methods. The transformers which are currently assembled for Welding Machines require hammering of the extruded Metal plate. This method requires large Human effort in form of Hammering. Hence the safety of the operator is also at a risk. The main purpose of this system is to automate the bending process so that almost negligible amount of Human Effort is required and the process becomes completely safe. This paper concentrates on the basic factors which should be considered while designing bending machine especially when sheet metal can’t be bent separately and having space constraint. Factors considered are force required, punch radius, reduction of spring back,

Desain dan Analisis Alat Bending V Sistem Hidro Pneumatik

The design of the pneumatic hydro system V bending tool serves as an alternative tool for bending plates replacing the manual bending method which is widely used in the industrial community, especially machining workshop workshops today. In this design the hydraulic jack bender is driven by a pneumatic cylinder so that the workload of the operator is lighter. As for the results of this design and analysis, a V bending tool with 750 mm frame height, 650 mm frame width, 150 mm hydraulic stroke length, and 5 mm diameter spring pull wire are obtained. In addition, the punch angle is 85o and the punch radius is 1.5 mm while the die angle is 85o, the width of the V die is 33 mm and the bending line capacity is 300 mm. The punch and die material chosen is steel AISI 1045.

Theoretical Investigation of the Bending Process of the Pre-Strained Metal Sheet

During the bending operation of the thin sheet materials by the punch with the near-to-zero radius the special technological operation should be carried out. It means that the metal sheet obtained a certain thinning value, which is usually done in the form of the channel-concentrator or groove by pre-drawing operation in a cold state. It follows to the pre-straining and strengthening of the material. The authors investigated the strain hardened sheet's area after roll forming process theoretically, and obtained the strain-stress distribution inside the sheet during the bending operation. It was found out that the increase of the prior deformation during pre-straining in the bend layer follows to the increase of the radial and tangential stresses and displacement of the neutral axis inside the blank during bending operation. As a result, the bending moment changes its values depends on the punch radius and strain hardening.

Pengaruh Sudut Punch dan Ketebalan Pelat terhadap Springback pada Bending V

The bent plate is inseparable from the phenomenon that determines the size of the resulting bending angle. This phenomenon is called springback. Springback is a condition that occurs on a sheet plate when bending is done where after the punch load is removed the bent sheet plate has a tendency to return to its original form. Mini brake bending V tool with a hydraulic jack system produces springback of 1-5 degrees for punch angle 85 ° radius 2.5 mm and carbon steel material St 42 at thickness 3, 4 and 5 mm. Therefore, this study was conducted to find out how the influence of punch angle and plate thickness on springback. The limitation problem in this study is the thickness of the plates used 2 and 4 mm. The type of method used is bending V bottoming with a die angle of 90 °, the punch angle used is 80, 85, and 90, the punch radius used is 2, 4 and 6 mm, and the plate material used is carbon steel. The research method starts from designing die set, punch and die test aids, and making test specimens, then bending test, bending angle and springback measurements are carried out. Based on the research conducted, the greater the punch angle, the smaller springback produced and the thicker the plate, the smaller springback produced tends to be smaller, where the smallest springback is obtained on a plate thickness of 6 mm with a punch angle of 90 ° 4 mm radius obtained -0.31o.

Experimental study on bending behaviour of aluminium-copper clad sheets in V-bending process

The bimetallic sheets are used in the industrial sheet metal products to meet the demands of multi-functionality. The bending behaviour of bimetallic sheet is contributed by individual layers of the sheet and it is entirely different from the monolithic material. In this study, V-bending experiments are carried out to understand the springback, bend force and thickness change of Al-Cu clad sheets. The effect of different parameters such as sheet thickness, sheet setting condition, die angle, die opening and punch radius have been investigated. The results indicated that springback is more for smaller die angle, wider die opening and larger punch radius. Increase in die angle, increase in die opening or decrease in punch radius decreases the bend force. The clad sheet thickens at Al/Cu setting condition whereas it thins at Cu/Al setting condition. This thinning or thickening of the sheet influences the springback and bend force.

Simplified springback prediction of thick sandwich panel

Springback is one of the most important design behavior in air-bending processes. The sandwich panel exhibits more complicated bending and springback behavior due to substantial differences in mechanical properties between the foam core and the metallic skin sheet. In this paper, we will not only propose a semi-analytical model in order to easily predict springback in air-bending process of steel/polyurethane/steel sandwich panel, but also we will carry out experiments to measure springback amount. The semi-analytical model results and the experiment findings proved to be in a good agreement. In addition, numerical simulations and experiments were conducted to investigate the effects of punch radius, die opening, and the foam thickness on springback.