Identification of Friction Law to Model Orthogonal Cutting

Abstract

A first approach of tool-chip interface behaviour for high-speed machining modelling has been carried out by Al Brocail and 2010 and an empirical friction law has been first determined. This law has been established for high temperatures (initial sample temperature equal to 750 K) and low sliding velocities (less than 0.5 m.s-1) and an extrapolation has been considered for higher velocities. This article intends to determine an empirical friction law for low temperatures (ambient) combined with high sliding velocities (up to 1.5m.s-1) by means of a tribometer developed by Meresse and Al. A new experimental device is designed to carry out several tests and simulate the friction behaviour at the tool-chip interface. The experimental results are compared with a numerical model and an iterative method is used to minimize the error between experimental and numerical simulations on normal and tangential forces. This method allows to recover a Coulomb friction coefficient which is associated to local pressure, temperature and sliding velocity. The completion of several tests provides an empirical friction law for high sliding velocities and low temperatures.