Design and dynamic characterization of composite material dampers for parting-off tools

This paper introduces a novel design for parting-off tools and the method to characterize their performance. The principle followed in the design phase was to enhance the damping capability minimizing the loss in static stiffness through implementation of composite material interfaces. The tool has been characterized by the dynamic characteristics criterion, i.e. frequency and damping ratio, of the machining system, as well as the roughness of the machined surface criterion. This paper demonstrates a new model-based method for characterizing the machining system dynamic properties, applied, in this sThe presented mathematical model of the machining system is based on the data recorded by a microphone during operational conditions. In this way, a step beyond the classical method of analyzing the dynamics of a machining system, which separately identifies the structural and process parameters is taken. The analyses together with the experimental results proved that the parting-off tool was able to machine over a wide range of cutting parameters. It was found that the limiting factor for increasing cutting parameters is not the damping capability of the tool but the tool clamping system stiffness and the workholding system dynamic properties. This implies that, in order to further optimize the machining performance, it is vital to take consideration not only the tool-clamp-turret system but the whole machining system.