Validation of a finite element model of the cold roll forming process on the basis of 3D geometric accuracy

Abstract Ultra-high strength steel (UHSS) pre-notched sections are getting growing popularity in the automotive industry with the development of automotive lightweight. However, the springback of UHSS products is large, and the existence of holes also has an effect on the springback. Accurate prediction of springback of UHSS pre-notched products in cold roll forming ( CRF ) is a key issue to be solved. In this paper, the effect of holes on the springback of UHSS in CRF is discussed by simulation and experiment. The finite element model of pre-notched car threshold was constructed, and its accuracy was validated by continuous CRF experiment. The mathematical model of variable elastic modulus determined by tensile tests of martensite (MS) 1300 was applied in finite element model. The accuracy of springback was improved by 15% in the hole region by using variable elastic modulus . Several forming schemes were designed to research the effect of different features on the springback in the hole region. The results show that the existence of holes reduces the springback and the effect is different at different positions of the car threshold. The springback in the hole region decreases with the increase of the number of stands, the strip thickness and the hole diameter, and with the decrease of the distance between stands and the distance between holes. This study provides a help for reducing the influence of holes on the springback and improving the forming precision of pre-notched sections in the actual production of CRF.

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Experimental and numerical investigation of cold roll forming process

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/758/1/012067 ◽

2020 ◽

Vol 758 ◽

pp. 012067

Author(s):

Mohanraj Murugesana ◽

Muhammad Sajjadb ◽

Dong Won Jung

Keyword(s):

Numerical Investigation ◽

Roll Forming ◽

Cold Roll Forming ◽

Forming Process ◽

Cold Roll ◽

Roll Forming Process

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Experimental study of bowing defects in pre-notched channel section products in the cold roll forming process

The International Journal of Advanced Manufacturing Technology ◽

10.1007/s00170-016-8547-y ◽

2016 ◽

Vol 87 (1-4) ◽

pp. 997-1011 ◽

Cited By ~ 14

Author(s):

Behrooz Shirani Bidabadi ◽

Hassan Moslemi Naeini ◽

Rouhallah Azizi Tafti ◽

H. Barghikar

Keyword(s):

Experimental Study ◽

Roll Forming ◽

Cold Roll Forming ◽

Forming Process ◽

Channel Section ◽

Cold Roll ◽

Roll Forming Process

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Simulation and optimization of the cold roll-forming process

10.1063/1.1766566 ◽

2004 ◽

Cited By ~ 8

Author(s):

Jinn-Jong Sheu

Keyword(s):

Roll Forming ◽

Cold Roll Forming ◽

Forming Process ◽

Simulation And Optimization ◽

Cold Roll ◽

Roll Forming Process

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A Method for Rapid Prediction of Edge Defects in Cold Roll Forming Process

Mathematics ◽

10.3390/math9161902 ◽

2021 ◽

Vol 9 (16) ◽

pp. 1902

Author(s):

Zhijuan Meng ◽

Yanan Fang ◽

Lidong Ma

Keyword(s):

Longitudinal Strain ◽

Roll Forming ◽

Cold Roll Forming ◽

Forming Process ◽

Yield Strain ◽

Cold Roll ◽

Rapid Prediction ◽

Edge Defects ◽

The Mean ◽

Roll Forming Process

In order to implement rapid prediction of edge defects in the cold roll forming process, a new analytical method based on the mean longitudinal strain of the racks is presented. A cubic spline curve with the parameters of the cumulative chord length is applied to fit the corresponding points and center points of different passes, and fitting curves are obtained. As the cold roll forming is micro-tension forming, the tensions between racks are ignored. Then the mean longitudinal strains between racks are obtained. By comparing the mean longitudinal strain between racks and the yield strain of the material, we can judge whether there are defects at the edges. Finally, the reasonableness of this method is illustrated and validated by an example. With this method, the roll forming effect can be quickly predicted, and the position where a greater longitudinal strain occurred can be determined. In order to prevent the defects, the deformation angles need to be modified when the result is beyond the yield strain. To further prove the correctness of the theory, the results of the analytical method are compared with the ones of the non-linear finite element software ABAQUS. The analytical results have the same trend as the finite element results. This method can provide useful guidance to the actual design process.

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Validation of a FEM Model for the Simulation of the Cold Roll Forming Process

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.651-653.219 ◽

2015 ◽

Vol 651-653 ◽

pp. 219-224 ◽

Cited By ~ 1

Author(s):

Antonio Formisano ◽

F. Capece Minutolo ◽

Antonio Caraviello ◽

Luigi Carrino ◽

Massimo Durante ◽

...

Keyword(s):

Plastic Deformation ◽

Technological Process ◽

Cross Section ◽

Circular Cross Section ◽

Roll Forming ◽

Cold Roll Forming ◽

Forming Process ◽

Fem Model ◽

Cold Roll ◽

Roll Forming Process

Cold roll forming is a process for plastic deformation, which allows realizing profiles, with a defined section and established length, from the plastic deformation of a metal sheet. The sheet is induced to cross several stands of rolls, arranged along the same axis of advancing. The rolls induce plastic deformation in the sheet and then lead it to the desired geometric configuration. In order to control the geometric parameters of the plate during the profiling, it was created a FEM model to simulate the final stage of the technological process, developed by an industrial production line of a company located in Naples (Italy), that sells tubes with several cross sections. In this phase, the semi-finished product, having a circular cross section, is forced to cross through four stands of rolls. In this way, it changes the geometric condition of the cross section from circular to square. The model was carried out using a non-linear calculation code, which allows analyzing the parameters of interest in the different process steps. The results, obtained numerically, were compared with the experimental ones through the measurement of five specimens, obtained directly from technological process. The values of percentage deviation, regarding the external dimension and the thickness, for each step of advancement, do not exceed the 3% of error. Then, the analysis results denote the capability to simulate the cold roll forming process using finite element method.

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