Thermal Scratch on Surface of SUS430 Stainless Steel Strip in Cold Rolling Process

Due to the requirement of magnetic properties of silicon steel sheets, producing high-precision size strips is the main aim of the cold rolling industry. The tapered work roll shifting technique of the six-high cold rolling mill is effective in reducing the difference in transverse thickness of the strip edge, but the effective area is limited, especially for a high crown strip after the hot rolling process. The six-high mill with a small work roll size can produce a strip with higher strength and lower thickness under a smaller rolling load. At the same time, the profile of the strip can be substantially improved. By advancing a well-established analytical method, a series of simulation analyses are conducted to reveal the effectiveness of a small work roll radius for the strip profile in the six-high cold rolling process. Through the analysis of flattening deformation and deflection deformation on the load, the change rule of the strip profile produced by the work roll with a small roll diameter can be obtained. Combined with theoretical analysis and industrial experiments, it can be found that the improvement effect of the small work roll radius on the profile of the silicon strip is as significant.

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Surface Brightness of Stainless Steel Strip by Axially Ground Rolls in Cold Rolling

Tetsu-to-Hagane ◽

10.2355/tetsutohagane1955.82.8_677 ◽

1996 ◽

Vol 82 (8) ◽

pp. 677-682 ◽

Cited By ~ 2

Author(s):

Hideo YAMAMOTO ◽

Yukihiko MATSUDAIRA ◽

Takashi SHIBAHARA ◽

Takeshi MASUI

Keyword(s):

Stainless Steel ◽

Cold Rolling ◽

Surface Brightness ◽

Steel Strip

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Proposal of Estimation System for Surface Brightness of Rolled Sheet in Stainless Steel Cold Rolling Process

Tetsu-to-Hagane ◽

10.2355/tetsutohagane1955.80.8_635 ◽

1994 ◽

Vol 80 (8) ◽

pp. 635-640 ◽

Cited By ~ 2

Author(s):

Akira AZUSHIMA

Keyword(s):

Stainless Steel ◽

Cold Rolling ◽

Surface Brightness ◽

Rolling Process ◽

Rolled Sheet ◽

Estimation System

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Investigation and Optimization of Load Distribution for Tandem Cold Steel Strip Rolling Process

Metals ◽

10.3390/met10050677 ◽

2020 ◽

Vol 10 (5) ◽

pp. 677 ◽

Cited By ~ 1

Author(s):

Xin Jin ◽

Changsheng Li ◽

Yu Wang ◽

Xiaogang Li ◽

Yongguang Xiang ◽

...

Keyword(s):

Genetic Algorithm ◽

Cold Rolling ◽

Prediction Model ◽

Load Distribution ◽

Rolling Mill ◽

Fitness Function ◽

Steel Strip ◽

Rolling Process ◽

Cold Rolling Mill ◽

Tandem Cold Rolling

In order to improve the cold rolled steel strip flatness, the load distribution of the tandem cold rolling process is subject to investigation and optimization. The strip deformation resistance model is corrected by an artificial neural network that is trained with the actual measured data of 4500 strip coils. Based on the model, a flatness prediction model of strip steel is established in a five-stand tandem cold rolling mill, and the precision of the flatness prediction model is verified by rolling experiment data. To analyze the effect of load distribution on flatness, the flatness of stand 4 is calculated to be 7.4 IU, 10.6 IU, and 16.8 IU under three typical load distribution modes. A genetic algorithm based on the excellent flatness is proposed to optimize the load distribution further. In the genetic algorithm, the classification of flatness of stand 4 calculated by the developed flatness prediction model is taken as the fitness function, with the optimal reduction of 28.6%, 34.6%, 27.3%, and 18.6% proposed for stands 1, 2, 3, and 4, respectively. The optimal solution is applied to a 1740 mm tandem cold rolling mill, which reduce the flatness classification from 10.8 IU to 3.2 IU for a 1-mm thick steel 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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Effect of Cold Rolling Process on the Microstructure and Corrosion Behaviors of 316L Stainless Steel in Simulated Body Fluids

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.548-549.310 ◽

2014 ◽

Vol 548-549 ◽

pp. 310-315

Author(s):

W.M.F.W. Mohamad ◽

M.Z. Selamat ◽

B. Bundjali ◽

M. Musa

Keyword(s):

Stainless Steel ◽

Cold Rolling ◽

316L Stainless Steel ◽

Rolling Process ◽

Optical Microscope ◽

Body Fluids ◽

Breakdown Potential ◽

Corrosion Behaviors ◽

Cold Rolled ◽

Simulated Body Fluids

This present paper is aims to study the influence of cold rolling process on the microstructure and corrosion behaviors of 316L stainless steel using potentiodynamics polarization testing techniques. The steel with initial thickness of 2.0 mm was unidirectional cold rolled to 10%, 30% and 50% reduction in thickness. The corrosion behaviors of the cold rolled steels were evaluated in phosphate buffered saline (PBS) as their simulated body fluids environment. The pH and temperature of the solution was maintained at 7.31 and 37°C and took approximately 5 hours for each individual test. The microstructure observations of the steels were studied using optical microscope and scanning electron microscopy (SEM). The results showed that the cold rolling process has modified the microstructure of 316L stainless steel by producing extensive surface defects. The microstructure modifications of the cold-rolled steel caused to enhance the corrosion resistance by lowering its corrosion rate to 23% and reduce the pitting resistance by lowering its breakdown potential to 61%. The pit corrosion was extensively appeared after reaching the breakdown potential.

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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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