Vibration analysis and numerical simulation of rolling interface during cold rolling with unsteady lubrication

摘要

The friction characteristics of rolling interface play a considerable role in rolling stability. In this work, vertical vibration speed is introduced into the Karman equation. An unsteady lubrication model considering entraining and squeezing effect is proposed. Additionally, a dynamic chatter model is developed by coupling the improved rolling force and unsteady lubrication model. The verification results at the micro- and macro-scales indicate that this chatter model has high accuracy. The effects of main process parameters, such as reduction, back tension and viscosity, on the mill stability were analyzed. Moreover, the changes in parameters and tribological characteristics due to unstable rolling process were investigated. The work concludes that the rapid change of lubrication state and friction stress result in vibration intensification.