Forecasting the mean flow stress of carbon and low-alloy steels in hot rolling on a strip mill

In this study, a improved mathematical model was developed for Nb-Ti microalloyed steel during hot rolling simulation. Using the compression test, the dynamic and static recrystallization characteristics of Nb-Ti microalloyed steel were studied. Though multi-pass hot rolling simulation, it is found that the recrystallization during hot rolling can play an important role, it can make the mean flow stress lower and refine the grains. And respective comparison between calculated and measured data of microstructure showed some of the validation of the built model. Meanwhile, the evolution characteristic of average austenite grain size during hot rolling can be achieved by theoretical model and experiment.

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Mathematical Modeling of the Mean Flow Stress during the Hot Strip Rolling of Ti-Nb IF Steels

Materials Science Forum ◽

10.4028/www.scientific.net/msf.426-432.3837 ◽

2003 ◽

Vol 426-432 ◽

pp. 3837-3842

Author(s):

Fulvio Siciliano ◽

Ronaldo Barbosa

Keyword(s):

Mathematical Modeling ◽

Flow Stress ◽

Mean Flow ◽

Hot Strip Rolling ◽

Strip Rolling ◽

Hot Strip ◽

Mean Flow Stress ◽

The Mean

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Hot Torsion Tests - A Reliable Rolling Simulation Method for C-Mn Steels

Materials Science Forum ◽

10.4028/www.scientific.net/msf.879.1783 ◽

2016 ◽

Vol 879 ◽

pp. 1783-1787 ◽

Cited By ~ 2

Author(s):

Fulvio Siciliano ◽

Brian Allen ◽

David Ferguson

Keyword(s):

Flow Stress ◽

Hot Deformation ◽

Simulation Method ◽

Absolute Temperature ◽

Mean Flow ◽

Torsion Testing ◽

Torsion Mode ◽

Mean Flow Stress ◽

The Mean ◽

Hot Torsion

Torsion tests have been proven to be a successful method to simulate the hot rolling of steels. Simulation work performed at a laboratory scale together with the analysis of the resulting mean-flow-stress behavior, leads to important metallurgical information to be considered during full-scale rolling processes. In this work, two different hot deformation schedules of C-Mn steels have been performed on a Gleeble simulation system in hot torsion mode. In addition to the torsion tests, the mean-flow-stresses of industrial rolling data were analyzed. Industrial hot deformation schedules simulated using hot torsion and the mean-flow-stress values were plotted versus the inverse of absolute temperature in the same graph. All points match the same behavior showing that torsion testing is a reliable hot working simulation method.

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Modeling of the Microstructural Evolution and Mean Flow Stress during Thin Slab Casting/Direct Rolling of Niobium Microalloyed Steels

Materials Science Forum ◽

10.4028/www.scientific.net/msf.500-501.221 ◽

2005 ◽

Vol 500-501 ◽

pp. 221-228 ◽

Cited By ~ 6

Author(s):

Fulvio Siciliano ◽

L.L. Leduc

Keyword(s):

Flow Stress ◽

Microalloyed Steels ◽

Hot Strip Mill ◽

Thin Slab ◽

Mean Flow ◽

Thin Slab Casting ◽

Slab Casting ◽

Mean Flow Stress ◽

Direct Rolling ◽

The Mean

Mill logs obtained from the Hylsa CSPTM (thin slab casting/direct rolling – TSC/DR) mill were examined so that the mean flow stresses at each pass were calculated using the Sims equation modified to take into account the forward slip ratio, the redundant strain and the work roll flattening. The mean flow stresses were then compared to predicted values obtained from a model. The microstructures during the CSP process were predicted by a mathematical model which was initially derived for conventional slab/roughing mill/hot strip mill (HSM) processing route. The adapted model takes into account the deformation of the as-cast structure in the finishing CSP mill, by using particular microstructural equations to calculate the softening kinetics and grain sizes. The main metallurgical features such as the occurrence of Nb(C,N) precipitation, the softening mechanism which takes place (static or metadynamic recrystallization) as well as the strain accumulation between passes were calculated. The mean-flow-stress results obtained from the calculations are in good agreement with the mill data. The present analysis indicates that it is possible to produce fine-grained microalloyed steels with homogeneous microstructure in thin slab casting/direct rolling processing.

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Effect of Dynamic Transformation on the Mean Flow Stress

steel research international ◽

10.1002/srin.201200166 ◽

2012 ◽

Vol 84 (3) ◽

pp. 253-258 ◽

Cited By ~ 14

Author(s):

John J. Jonas ◽

Chiradeep Ghosh ◽

Vladimir V. Basabe

Keyword(s):

Flow Stress ◽

Mean Flow ◽

Dynamic Transformation ◽

Mean Flow Stress ◽

The Mean

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New Phenomenological Model of Hot Mean Flow Stress

High Temperature Materials and Processes ◽

10.1515/htmp-2012-0041 ◽

2013 ◽

Vol 32 (2) ◽

pp. 133-138

Author(s):

Ivo Schindler ◽

Petr Kawulok ◽

Stanislav Rusz ◽

Jiří Plura ◽

Zdeňek Vašek ◽

...

Keyword(s):

Flow Stress ◽

Hot Rolling ◽

Effective Strain ◽

Single Equation ◽

Mean Flow ◽

Strain And Strain Rate ◽

Wide Range ◽

Mean Flow Stress ◽

Experimental Values ◽

Fast Prediction

AbstractBased on the measurement of roll forces during the laboratory hot rolling of flat samples graded in thickness, the new phenomenological type of mean flow stress model was developed and applied on plain-carbon and HSLA steels. The obtained models describe with a very good accuracy the hot deformation resistance characteristics in the temperature range 1123 to 1463 K, large effective strain, and strain rate in the useful range of approximately 10 to 100 s−1. Difficulty in the mathematical description of the influence of temperature on mean flow stress in the wide range of temperature by a single equation was solved by introducing another constant in the temperature member of the conventional model. The newly proposed model solves by phenomenological means a frequent problem of heteroscedasticity of relative deviations between the calculated and experimental values of mean flow stress values depending on temperature. It becomes more reliable from the viewpoint of the operational application, e.g. fast prediction of mean flow stress values and power/force parameters necessary in the steering systems of hot rolling mills.

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