A Geometric Approach to Modelling Friction In Metal Forming

When simulating metal fanning processes It is common practice to describe the friction by using the Coulomb or Tresca model and to assume that the conditions are constant throughout the process. This paper describes an alternative approach that seeks to describe friction by modelling the geometric surface roughness of the tools. Using the ring test analytically a relationship has been established between surface geometry and the friction factor. This model has been validated experimentally also using the ring test. Such a system provides an opportunity to model friction more flexibly and accurately.