In this paper, the wear of work roll in HOT plate ROLLING is introduced and the parameters affecting wear mechanisms in HOT strip mill are investigated. In addition, different wear mechanisms in HOT ROLLING and the differences between these mechanisms in different stands are explained. Using the finite element method and the ROLLING equations, a work roll wear model is proposed. Wear is modeled using the resultant pressure distribution along the roll barrel. To obtain the tentative coefficient, summation of wear in each pass schedule is obtained and calibrated via actual wear of samples tested in the Mobarakeh Steel Company. Finally, the theoretical wear values are compared with those of the experiment. The predicted wear profiles are found to be in good agreement with those of the experimental measured values.

The HOT ductility of IMI834 alloy in two conditions of first HOT ROLLING and second HOT ROLLING has been studied by conducting tensile tests with a strain rate of 0.1 s−1 and temperature range of 800–1000°C. In first HOT ROLLING condition, IMI834 alloy showed little HOT ductility in the temperature range 800–900°C and ductility loss occurred at 850°C. In second HOT ROLLING condition, HOT ductility increased at all temperatures and ductility loss is not occurred. Especially at 900°C, HOT ductility increased from 31% in first HOT ROLLING to 95% in second HOT ROLLING.

The effect of chemical composition and the HOT ROLLING operations on the microstructure and mechanical properties of in situ aluminum matrix composite with Mg2Si phase as the reinforcement was studied. It was revealed that the modification by phosphorous results in the rounder (more spherical) primary and secondary (eutectic) magnesium silicide intermetallics. During HOT ROLLING, the primary particles underwent mechanical fragmentation and the fragmented particles moved along the ROLLING direction. Moreover, the eutectic Mg2Si fragmented and uniformly dispersed in the microstructure. By increasing the reduction in thickness, it was almost impossible to distinguish primary particles from eutectic ones due to excessive fragmentation of particles. These observations were related to the brittleness of Mg2Si phase and the elongation of the matrix grains during ROLLING. The grain size of the matrix also changed due to the occurrence of recrystallization and the average grain size decreases from ~ 90 μ m to 7 μ m for the 98% rolled sample. The change in mechanical properties was related to the fragmentation of particles, destroying the eutectic network, magnificent grain refinement of the matrix, the retardation of recrystallization by the dispersed particles at grain boundaries of aluminum grains, and the fast cooling of thin sheets at high reductions in thickness.

Obtaining temperature distribution data of slabs under ROLLING is essential as the mechanical and metallurgical properties of the metal under this process vary with temperature. Using the control volume method, a mathematical model is employed in this study to predict slab temperature in the HOT roll process at Mobarakeh Steel Company. The effects of different parameters including the heat resulting from plastic deformation and slab material are investigated. Additionally, heat conduction along the ROLLING direction in the slab, ignored in most previous studies, is included in our investigation. The study indicates the importance of this term in the accuracy of the results obtained.

In the present investigation, a HOT ROLLING process of AA5083 aluminum alloy is simulated. The approach is based on the thermo-mechanical analysis of the problem using the Finite Element Method (FEM). The temperature distribution in the roll and the slab, the stress, strain and strain rate fields, are extracted throughout a transient analysis of the process. The main hypotheses adopted in the formulation are: The thermo-viscoplastic behavior of the material, expressed by the Perzyna constitutive equation and ROLLING under plane-deformation conditions. The main variables that characterize the ROLLING process, such as the geometry of the slab, load, ROLLING speed, percentage of thickness reduction, initial thickness of the slab and friction coefficient, have been expressed in a parametric form, giving good flexibility to the model. The congruence of the results has been evaluated using experimental and theoretical data available in the literature.

Dimensional control of the work-piece in steel industry is of important interest. The main aspects in overcoming the thickness control are variations in material strength due to variations in chemical composition, work-piece temperature, reduction and the strain rate applied to the work-piece. In this paper based on the main parameters affecting the ROLLING force an attempt been made to give a more accurate prediction for the flow stress in a steel ROLLING finishing mill. Predicted values of the model are compared with those of the experimental values which are shown to be in good agreements.

Work rolls in the HOT ring ROLLING process are susceptible to various damages due to the contact with HOT metal. Thermo-mechanical fatigue is one of these damages. In order to predict failure resulting from the thermo-mechanical stress in the work rolls, the developed code in ABAQUS was used. A comparison between three-and two-dimensional models was made and also, thermal and thermo-mechanical responses of work rolls with variable boundary conditions were investigated. The results demonstrated that by applying mechanical and thermal loads separately or simultaneously, the response of work rolls is completely different. In the mandrel, the location of the maximum equivalent stress is on the surface, while the location of equivalent maximum stress is on the subsurface of the main roll. Upon utilizing cumulative damage rules and the stress-life method, the thermo-mechanical fatigue life was estimated. The cumulated damage to the surface of the mandrel was higher than that to subsurface regions. In contrast to the mandrel, the cumulated damage to the subsurface of the main roll was higher than that to the surface regions. In HOT ring ROLLING machines, these locations are prone to crack initiation as a result of the thermo-mechanical fatigue of the work rolls.

Microstructure control is one of the most challenging issues in forming processes. It affects the quality enhancement of the product directly. The Finite Element Method (FEM) is an appropriate approach in forming analysis which can be applied for predicting microstructure. Many studies have addressed this issue through mathematical and physical models. In addition, several constitutional equations have been developed to model parameters such as grain growth, dislocation density, and recrystallization, etc. In this article, after choosing the appropriate constitutional equations and extracting the required relationships, a subroutine in the Fortran language has been developed. In the next step a ROLLING process with defined conditions have been analyzed in the finite element software, and the microstructural parameters have been investigated. Then the results were compared with the laboratory data and a remarkable similarity was observed. Finally, the effect of changes in friction, thickness reduction and roller speed have also been investigated.