Numerical simulation of dynamic recrystallization behavior of 316L stainless steel under flexible rolling state

With the rapid development of continuous rolling technology, the rigid connection of production equipment-techniques often results in roll wear and frequent shutdowns for roll replacement, which restricts the development of its technical advantages. In this paper, ASTM-316L is used as the experimental steel, based on the numerical simulation technology to carry out the numerical simulation and process optimization research of online roll changing of flexible rolling, comprehensive material high-temperature plastic flow behavior, coupling recrystallization kinetic model embedded in Deform-3D software, to establish a multi-field coupled collaborative control model of online roll changing of flexible rolling, simulating the impact of online roll change on the strip DRX behavior. The results show that the reduction rate of the online roll change, the roll exit speed, the roll input speed, and the deformation temperature have essential effects on the microstructure uniformity of the strip along the thickness direction. Smaller reduction rate, faster roll exit speed, slower roll input speed, and lower deformation temperature are all beneficial to reduce the gradient of DRX volume fraction in the core and surface of the strip and avoid stress concentration and instability. The roll diameter has little effect on the DRX volume fraction gradient at the core and surface of the strip. Therefore, it is necessary to control the online roll changing process of flexible rolling according to the actual rolling process, considering the load of the rolling mill and the mass of the rolls. The research on the recrystallization behavior of online roll changing in this paper can provide a theoretical basis for designing and optimizing the microstructure control of flexible rolling.