Numerical Analysis of Residual Stresses in Hot Rolled Strip subjected to Run-Out-Table Cooling Process.

摘要

This is the study on the prediction of residual stresses in hot rolled strip after Run-Out-Table (ROT) cooling. A ROT with cooling devices usually resides between the last finishing stand and the down coiler. The quality of the final product, such as the metallurgical and mechanical properties and the flatness of the strip, may vary significantly depending upon how the strip is cooled down when it passes through ROT. With precise analysis of this cooling process, residual stresses of strip can be obtained and the final properties of the strip can be improved by controlling the mechanism of residual stresses evolution and reducing those stresses. For the precise modeling of ROT cooling process, the interaction among the thermal, mechanical, and metallurgical behavior and the three dimensional nature of the problem must be considered. In this study, integrated model has been developed and a series of simulation is conducted to verify the validity of the proposed model. Integrated model consists of four parts, thermodynamics, phase transformation, heat transfer and elastic-viscoplastic deformation analysis and each component models are mutually affected by the connection of input and output parameters during ROT cooling process.