A realistic friction model for lubricated cold rolling process with front and back tension is developed. The model combines a rigid-plasticity finite element code with a lubrication analysis. The rolls are assumed to be rigid and uniform deformation and isothermal conditions are assumed to prevail. The surface roughness effect on lubricant flow is included by using a average Reynolds equation. The active lubrication regime and appropriate friction factor can then be expressed in terms of internal interface variables in addition to the more traditional external variables. These internal variables include mean lubricant film thickness, workpiece roughness and roll roughness. The external variables are interface pressure and sliding speed. Numerical results using the coupled code such as roll separating force and roll torque under different rolling conditions are compared with experimental investigation. The simulation results are in good agreement with experimental data.
- Lubrication analysis
- Surface roughness