Application of the XFEM to Predict the Edge Crack Propagation of Steel Sheet in the Cold Rolling Process

Silicon steels tend to develop edge cracks during cold rolling, which need to be removed and cause rupture of the steel in the rolling mill. Hence, it is necessary to understand the formation of edge cracks. The damage distribution and the initiation and propagation of edge cracks occur around the notch tip during cold rolling process was investigated by using GTN damage model. The damage parameters f0, fcand fFare determined by tension experiments and SEM observation. The influence of various rolling parameters on damage distribution and crack length was simulated by using ABAQUS. The numerical results show that the GTN damage model is available to prediction the initiation and propagation of edge cracks during rolling process. Parametric study carried out in this present work reveals that the possible occurrence of edge cracks is higher at larger reduction, higher friction coefficient, smaller roll radius and stronger unit tension. The simulation and experimental results have a good agreement .

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Study on 3D Edge Crack Extension Simulation in Cold Rolling with the Cohesive Zone Model

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.853.101 ◽

2016 ◽

Vol 853 ◽

pp. 101-105

Author(s):

Da Qian Zan ◽

Quan Sun ◽

Hong Liang Pan ◽

Jian Jun Chen ◽

Zheng Dong Wang

Keyword(s):

Cold Rolling ◽

Cohesive Energy ◽

Cohesive Zone ◽

Edge Crack ◽

Crack Extension ◽

Cohesive Zone Model ◽

Rolling Process ◽

Zone Model ◽

Hybrid Technique ◽

Cohesive Stress

In the cold rolling process, the edge crack extension can cause the strip rupture completely due to the micro manufacturing defects in the edge. It can greatly impact on the production efficiency and cause the huge economic loss. Thus predicting the edge crack extension behavior becomes important to cold rolling industry. In this paper, a 3D extended finite element method (XFEM) based on the cohesive zone model (CZM) was used to study the edge crack extension under the non-reversing two-high mill cold rolling experiment condition. A bi-linear traction-separation law was utilized which is primarily given by the CZM parameters including the cohesive stress, T0 and the cohesive energy, Γ0. The cohesive stress was determined by hybrid technique of the thin-plate tension test and FEM simulation. The cohesive energy was obtained by the In-Situ SEM three points bending experiment. Different reductions were the mainly analysis factor which can study the extent of the edge crack extension by presetting the edge notch. By comparing the experimental and simulation results, they agreed well with each other. It illustrated that the CZM can provide accurate predictions for the edge crack extension in the cold rolling process. Parametric analysis was carried out and showed that the extent of the crack extension increases with the increasing of the reduction ratio.

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Study on edge crack propagation during cold rolling of thin strip by FEM

10.1063/1.3457536 ◽

2010 ◽

Cited By ~ 2

Author(s):

H. B. Xie ◽

Z. Y. Jiang ◽

D. B. Wei ◽

A. K. Tieu ◽

F. Barlat ◽

...

Keyword(s):

Cold Rolling ◽

Crack Propagation ◽

Edge Crack ◽

Thin Strip

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Influence of Cold Rolling Process on Mini Spangle Formation of 55%Al-Zn Alloy Coating Steel Sheet

Materials Science Forum ◽

10.4028/www.scientific.net/msf.936.171 ◽

2018 ◽

Vol 936 ◽

pp. 171-177

Author(s):

Tai Xiong Guo ◽

Xue Qiang Dong ◽

Chang Rong Ran

Keyword(s):

Cold Rolling ◽

Steel Sheet ◽

Steel Substrate ◽

Steel Strip ◽

Alloy Coating ◽

Compound Layer ◽

Rolling Process ◽

Intermetallic Compound Layer ◽

Rolling Oil ◽

Zn Alloy

According to that mini spangle is the most common defect affecting the appearance quality of hot-dip 55%Al-Zn alloy coated steel sheet, industrial experiments and statistical analysis were done to investigate the influence of cold rolling process on the formation of mini spangle. The results show that, with the decrease of rolling oil concentration, the increase of rolling time, and the increase of rolling pass, the probability of mini-spangle formation increases. Due to the different equipment conditions, the probability of mini-spangle formation on the upper and lower surfaces of steel strip is different. The reason of mini-spangle formation lies in the presence of carboxylates (R-COO-Fe) result from the residual emulsion on the surface of cold rolled steel strip. The carboxylates may interfere with the interfacial reaction between the steel substrate and Al-Zn bath, and result in more convex Fe5Si2Al20 phases formed on the surface of intermetallic compound layer. The Fe5Si2Al20 phases may provide more heterogeneous nucleation sites for the formation of Al-rich dendrites and lead to the formation of mini spangle.

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Investigation on Validity of J-Integral of Edge Crack under Cold Rolling Condition

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.556-562.696 ◽

2014 ◽

Vol 556-562 ◽

pp. 696-699

Author(s):

Jian Jun Chen ◽

Xiao Xue Li ◽

Hong Liang Pan

Keyword(s):

Cold Rolling ◽

Edge Crack ◽

Crack Tip ◽

Simulation Method ◽

Rolling Process ◽

J Integral ◽

Strip Steel ◽

Failure Region ◽

Incremental Theory Of Plasticity

In this paper the characterization of the edge crack in the strip steel are studied by using numerical simulation method. The developments of the stress and strain near the crack tip are obtained and the value of the J-integral of edge crack under the rolling process is then examined. FE simulation result shows that the J-integral is not always path independent in the whole rolling process. When the crack is far away from the roller, the J-integral is path independent. When the crack enters the cold rolling region, the unload phenomena will occur near the crack tip which cause the incremental theory of plasticity failed and the conservation of the J-integral is not valid any more. The J-integral failure region is then determined by a series of FE simulations.

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Prediction of Edge Crack in Cold Rolling of Silicon Steel Strip Based on an Extended Gurson–Tvergaard–Needleman Damage Model

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4028827 ◽

2015 ◽

Vol 137 (2) ◽

Cited By ~ 2

Author(s):

Quan Sun ◽

Jianjun Chen ◽

Hongliang Pan

Keyword(s):

Cold Rolling ◽

Edge Crack ◽

Steel Strip ◽

Damage Model ◽

Rolling Process ◽

Reduction Ratio ◽

Shear Damage ◽

Gtn Damage Model ◽

Edge Cracking ◽

Roller Radius

Edge cracking is commonly observed in cold rolling process. However, its failure mechanism is far from fully understanding due to the complex stresses and plastic flow conditions of steel strip under the rolling condition. In this paper, an extended Gurson–Tvergaard–Needleman (GTN) damage model coupled with Nahshon–Hutchinson shear damage mechanism was introduced to investigate the damage and fracture behavior of steel strip in cold rolling. The results show that extended GTN damage model is efficient in predicting the occurrence of edge crack in cold rolling, and the prediction is more accurate than that of the original GTN damage model. The edge cracking behavior under various cold rolling process parameters is investigated. It comes to the conclusion that edge crack extension increases with the increase of the reduction ratio, tension and the decrease of the roller radius and friction coefficient. The influence of shear damage becomes more significant in rolling condition with a larger reduction ratio, smaller roller radius, lower friction force, and tension.

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