Evaluation of elastic-plastic deformation in HSS work roll under coupling of residual stress thermal stress and contact stress during hot rolling

Abstract

Fatigue damage such as crack and spalling on the work roll surface in hot rolling is caused by comprehensive action of residual stress, thermal stress and contact stress. In this work, a HSS work roll was studied based on the actual hot rolling condition, and high temperature performances of the work roll materials are considered. Finite element method was used to obtain the residual stress distribution of the work roll after quenching and tempering. Then, the coupling mechanism of residual stress, thermal stress and contact stress of the work roll in the bite region are analyzed by a transient thermomechanical model. The results showed that, the maximum equivalent strain and equivalent plastic strain appear at the exit of the bite region. And residual stress and thermal stress account for about 90% of the coupling stress. The accumulation of plastic deformation only occurs in the initial rolling, and the initial temperature influences the plastic deformation accumulation. Furthermore, abnormal rolling often leads to large plastic deformation on the roll surface.