Simulation of Thermal Stress and Fatigue Life Prediction of High Speed Steel Work Roll during Hot Rolling Considering the Initial Residual Stress

Metals

Yoshikazu Sano¹  Nao-Aki Noda¹  Kejun Hu²  Fuxian Zhu²  Jufang Chen²  Wenqin Han² 

[1] Department of Mechanical Engineering, Kyushu Institute of Technology, Kitakyushushi 804-8550, Japan;School of Materials and Engineering, Jiangsu University of Technology, Changzhou 213001, China;

关键词: work roll;    residual stress;    thermal stress;    thermal fatigue;    FEM;   

DOI  :  10.3390/met9090966

来源: DOAJ

【 摘 要 】

Considerable residual stress is produced during heat treatment. Compressive residual stress at the shell is conductive to improving the thermal fatigue life of a work roll, while tensile stress in the core could cause thermal breakage. In hot rolling, thermal stress occurs under the heating-cooling cycles over the roll surface due to the contact with the hot strip and water spray cooling. The combination of thermal stress and residual stress remarkably influences the life of a work roll. In this paper, finite element method (FEM) simulation of hot rolling is performed by treating the residual stress as the initial stress. Afterwards, the effects of the initial roll temperature and cooling conditions on thermal stress considering the initial residual stress are discussed. Lastly, the thermal fatigue life of a work roll is estimated based on the strain life model. The higher initial roll temperature causes a higher temperature but a lower compressive thermal stress at the roll surface. The surface temperature and compressive stress increase significantly in the insufficient cooling conditions, as well as the center tensile stress. The calculation of the fatigue life of a work roll based on the universal slopes model according to the 10% rule and 20% rule is reasonable compared with experimental results.

【 授权许可】

Unknown