A Model for Vibrations During Dry Sliding Friction

The occurrence of vibrations in tools during dry sliding friction is well known. A good understanding of this phenomenon leads to a better, possibly automatic, control of metal working operations. It is influenced by the dynamic characteristic of the equipment, machinery or test facility. In the present paper a relation for the acceleration of one of the sliding components is developed. The suggested model offers a physical explanation for the phenomenon of vibrations and screaming during dry sliding friction. It is based or plasticity theory and the surface geometry of the couple, as established from tests. Properties of the worn material are taken into account together with the dynamic characteristics of the experimental setup. With the normal force and the mass of the pinholder this leads to the frequency of the vibration. The friction tests have been carried cut using a sin-ring setup on a lathe equipped with force and acceleration transducers. The experiments appear to support the model. The phenomenon described has been applied succesfully to detect the end of tool life in drilling experimentally.