Numerical and Experimental Investigation into Hot Stamping of High Strength Steel Sheet for Auto B Pillar Reinforced Panel

2010 ◽  
Vol 129-131 ◽  
pp. 322-327 ◽  
Author(s):  
Zhong Wen Xing ◽  
Jun Jia Cui ◽  
Hong Sheng Liu ◽  
Chun Feng Li
Keyword(s):  
Process Parameters ◽  
High Strength Steel ◽  
Hot Stamping ◽  
High Strength ◽  
Fe Model ◽  
Blank Holder Force ◽  
Blank Holder ◽  
Coefficient Increase ◽  
Straight Wall ◽  
Good Agreement

Hot stamping is an innovative way to manufacture complex-shaped components of high strength steel (HSS) sheet with a minimum of springback, meanwhile, it can also obviously improve the tensile strength of the formed parts.The coupled thermo-mechanical FE model for hot stamping of HSS sheet for the B pillar was established by commercial software Pam-stamp. Dynamic explicit module was used to simulate the forming processes under different process parameters. The effects of process parameters on thinning of the blank were studied, the maximum thinning zones of the blank in hot stamping were analyzed. The results show that the thinning rates of the blank increase when the blank holder force(BHF) and friction coefficient increase, the maximum thinning zones appear at the straight wall and corner of the B pillar. The causal of blank thinning during hot stamping was analyzed. Experiments had been conducted with the process parameters obtained by simulation. The experimental and simulation results were in good agreement.

The Analysis on the Stamping Formability of High Strength Steel

2021 ◽  
Vol 885 ◽  
pp. 3-9
Author(s):  
Wen Yu Ma ◽  
Jian Wei Yang ◽  
Ye Yao ◽  
Yong Qiang Zhang ◽  
Jun Zhang
Keyword(s):  
High Strength Steel ◽  
High Strength ◽  
Blank Holder Force ◽  
Blank Holder ◽  
Variable Blank Holder Force ◽  
Automotive Part ◽  
Blank Shape ◽  
Shaped Blank

Recently the high strength steel has been applied in the automotive more and more widely. In this study, the effect of blank shape on the formability of an automotive part was analyzed. The three kinds of blank shapes were chosen, including a rectangular shaped blank, a blank with two corners cut straightly and a blank with two corners cut in curve. The effect of the variable blank holder force on the formability was studied. The four kinds of variable blank holder force were applied. The blank shape in this part is the blank with two corners cut curve. The results show that the blank with two corners curve is the most suitable. And the blank holder force from 1000 kN to 1500 kN is the most useful for the formability.

scholarly journals Study on forming process and spring back control of high strength sheet based on Dynaform

2018 ◽  
Vol 232 ◽  
pp. 02039
Author(s):  
cunping Liu
Keyword(s):  
Velocity Profile ◽  
High Strength Steel ◽  
High Strength ◽  
Steel Part ◽  
Drawing Process ◽  
Spring Back ◽  
Blank Holder Force ◽  
Forming Process ◽  
Blank Holder ◽  
Motion Mode

The drawing process of a high strength steel part without blank holder force was numerically simulated based on Dynaform. In present investigation, the drawing velocity and velocity profile motion of punch was studied by simulating the drawing operation of high strength steel part. The results show that restricting drawing velocity and controlling velocity profile motion of punch could all reduce the spring back. The measure of restricting drawing velocity could reduce non-pressure forming spring back about 31% and Trapezoidal motion mode of punch is the most beneficial to reduce spring back.

Springback Experimental Research of Advanced High-Strength Steel

2013 ◽  
Vol 842 ◽  
pp. 284-288
Author(s):  
Jun Yi Ke ◽  
Yu Qi Liu ◽  
Gui Li ◽  
Ting Du
Keyword(s):  
Yield Stress ◽  
Experimental Research ◽  
High Strength Steel ◽  
High Strength ◽  
Holding Time ◽  
Impact Factors ◽  
Advanced High Strength Steel ◽  
Blank Holder Force ◽  
Blank Holder ◽  
Springback Angle

Springback is one of the major problems of high strength steel.Based on the NUMISHEET’96 S_Rail standard examination questions,using the characteristics of the servo press 200T,the blank holder force,different pressure holding time and the holding times of advanced high strength steel DP280-440, DP340-590, DP400-780 are studied. By changing one of the three impact factors ,three group experiments are carried out.The experimental results show that the springback can change evidently with the increasing of the blank holder force and the holding times,but the holding time has little influence on the springback.What’s more,the springback angle of DP400-780 is the biggest ,proving the higher the yield stress,the bigger the springback angle.Therefore, in the stamping of advanced high strength steel, increasing the blank holder force and holding times are effective methods to solve the springback.

Influence of Temperature and Deformation on Phase Transformation and Vickers Hardness in Tailored Tempering Process: Numerical and Experimental Verifications

2014 ◽  
Vol 136 (5) ◽  
Author(s):  
B. T. Tang ◽  
Q. L. Wang ◽  
S. Bruschi ◽  
A. Ghiotti ◽  
P. F. Bariani
Keyword(s):  
Vickers Hardness ◽  
Hot Stamping ◽  
High Strength Steels ◽  
High Strength ◽  
Fe Model ◽  
Forming Technology ◽  
Water Recirculation ◽  
Die Temperature ◽  
Ultra High Strength Steels ◽  
Good Agreement

Hot stamping of quenchenable ultra high strength steels currently represents a promising forming technology for the manufacturing of safety and crash relevant parts. For some applications, such as B-pillars which may undergo impact loading, it may be desirable to create regions of the part with softer and more ductile microstructure. In the article, a laboratory-scale hot stamped U-channel was produced with segmented die, which was heated by cartridge heaters and cooled by chilled water recirculation independently. It can be concluded that in order to satisfy tailored mechanical properties by introducing regions, which have an increased elongation for improved energy absorption, the minimum die temperature should be no less than 450 °C. Optical micrographs were used to verify the microstructure of the as-quenched phases with respect to the heated die temperatures. For the cooled die region, the microstructure was predominantly martensite for all the die temperatures interested. With the increase of heated die temperature, there was a decrease of Vickers hardness in the heated region due to the increasing volume fractions of bainite. The finite element (FE) model was developed to capture the overall hardness trends that were observed in the experiments. The trends between the simulations and experiments were very similar, with acceptable differences in the magnitude of Vickers hardness. The transition widths were measured and simulated and there was a quite good agreement between experiment and simulation with almost the same value of 10 mm by taking heat conduction into account.

Study on the Hot Stamping of Rectangular Box with Ultra-High Strength Steel

2013 ◽  
Vol 763 ◽  
pp. 156-159
Author(s):  
Wei Chen ◽  
Zhi Feng Chen ◽  
Zhi Fu Cao ◽  
Tao Qi ◽  
Xiang Wang ◽  
...  
Keyword(s):  
High Strength Steel ◽  
Initial Temperature ◽  
Hot Stamping ◽  
High Strength ◽  
Stress And Strain ◽  
Minimum Thickness ◽  
Blank Holder ◽  
Punch Velocity ◽  
Ultra High Strength Steel ◽  
The Impact

Hot stamping of the ultra high strength steel (UHSS) was studied to meet the requirements of lightweight of automobile. The coupled thermo-mechanical model for hot stamping was established with ABAQUS. Initial temperature of tools (die, punch, blank holder) and stamping speed were studied to insure the impact on the thickness, stress and strain of blank. It shows that punch fillet area is easy to crack. With the temperature of tools increasing, the sheet minimum thickness increases first and then decreases. With the increase of punch velocity, the sheet minimum thickness increases. Compared with the initial temperature of tools, punch velocity has a greater impact on the thickness. The simulation results are in agreement with the experimental results and provide a theoretical basis for the practical stamping process.

scholarly journals Investigation of process parameters and plate local thickening on residual stresses in hot stamping process

2021 ◽  
Vol 22 ◽  
pp. 18
Author(s):  
Jinbo Li ◽  
Xiaohui Chen ◽  
Xianlong Liu
Keyword(s):  
Aluminum Alloy ◽  
Residual Stresses ◽  
Process Parameters ◽  
Hot Stamping ◽  
Experimental Methods ◽  
Small Radius ◽  
Blank Holder Force ◽  
Flat Plates ◽  
Blank Holder ◽  
Forming Temperature

In this paper, local-thickened plates are adopted for aluminum alloy square cups stamping with relatively low values of residual stresses and small radius at the bottom corner. By utilizing numerical and experimental methods, the effects of process parameters and plate local thickening on the residual stress distribution of hot stamped aluminum alloy square cups are studied. Furthermore, the influence of plate local thickening on the radius of bottom corner of square cups is also investigated. The results showed that with an increase in the forming temperature, blank holder force and die corner radius, residual stresses in hot stamped square cups can be reduced. The same effect can be achieved by decreasing the die entrance radius. As opposed to the flat plates, using local-thickened plates can not only reduce the residual stresses values in hot stamped square cups, but also decrease the radius at the bottom corner of square cups. When the optimized thickening scheme of plate is used, the smaller radius at the bottom corner, the lower residual stresses in the square cups are obtained.

Effect of Forming Parameters on Springback of Advanced High Strength Steel DP800

2014 ◽  
Vol 703 ◽  
pp. 182-186
Author(s):  
Nguyen Quang Minh
Keyword(s):  
Numerical Simulation ◽  
Friction Coefficient ◽  
High Strength Steel ◽  
Side Wall ◽  
High Strength ◽  
Advanced High Strength Steel ◽  
Blank Holder Force ◽  
Blank Holder ◽  
Thickness Increase ◽  
Suppression Effect

Springback is one of the main quality defects in the sheet forming. In this paper, numerical simulation is used to analyze the effects of blank holder force, friction coefficient, blank thickness, die corner radius and stroke on springback. The effect of blank holder force and blank thickness on springback is obvious. Springback decreases as the BHF and blank thickness increase. Increasing friction coefficient between tools and blank shows a good suppression effect on springback. Larger die corners increase the curvature of side wall and worsen the springback, but the springback of flange is reduced. The greater the stroke is, the larger the final springback will be.

Quenchability improvement and control simplification by ice mandrel in hot stamping of ultra-high strength steel hollow parts

2021 ◽  
Vol 64 ◽  
pp. 916-926
Author(s):  
Ali Talebi-Anaraki ◽  
Tomoyoshi Maeno ◽  
Ryohei Ikeda ◽  
Kazui Morishita ◽  
Ken-ichiro Mori
Keyword(s):  
High Strength Steel ◽  
Hot Stamping ◽  
High Strength ◽  
Ultra High Strength Steel ◽  
And Control

Enhancement of the tensile shear strength for joining low-ductility aluminium to high-strength steel by using electrically-assisted mechanical clinching (EAMC)

2021 ◽  
pp. 095440542199565
Author(s):  
Abozar Barimani-Varandi ◽  
Abdolhossein Jalali Aghchai
Keyword(s):  
Shear Strength ◽  
High Strength Steel ◽  
High Strength ◽  
Fe Model ◽  
Tensile Shear Strength ◽  
Tensile Shear ◽  
Electroplastic Effect ◽  
Fracture Displacement ◽  
Electrically Assisted ◽  
Mechanical Clinching

The present work studied the enhancement of the tensile shear strength for joining AA6061-T6 aluminium to galvanized DP590 steel via electrically-assisted mechanical clinching (EAMC) using an integrated 2D FE model. To defeat the difficulties of joining low-ductility aluminium alloy to high-strength steel, the electroplastic effect obtained from the electrically-assisted process was applied to enhance the clinch-ability. For this purpose, the results of experiments performed by the chamfering punches with and without electrically-assisted pre-heating were compared. Joint cross-section, failure load, failure mode, fracture displacement, material flow, and failure mechanism were assessed in order to study the failure behaviour. The results showed that the joints clinched at the EAMC condition failed with the dominant dimpled mechanism observed on the fracture surface of AA6061 side, achieved from the athermal effect of the electroplasticity. Besides, these joints were strengthened 32% with a much more fracture displacement around 20% compared with non-electrically-assisted pre-heating.

Sign in / Sign up

Export Citation Format

Share Document