Estudo numérico do controle passivo de vibrações em torneamento mecânico a partir de materiais piezoelétricos

Abstract

Chatter is a self-excited vibration that is found in several machining processes and for this reason it is one of the main causes for bad superficial quality on the workpiece. Therefore, the need of minimizing vibrations has been an increasing demand to industries, that are always searching for efficiency in machining processes and products with a better surface quality. In conventional turning operations, these mechanical vibrations happens very frequently and one of the solutions to reduce it is on the use of piezoelectric materials combined to a shunt circuit. This set can be seen as a mechanism of passive damping when correctly projected and it has the feature of converting the mechanical vibration energy to electrical energy, which is dissipated through heat by the Joule effect. The objective of this paper is the modeling and the study of this device, which is able to reduce mechanical vibrations over the cutting tool in turning opeartions resulting in a better finishing on the workpiece. As a result, this work shows the functionality of the piezo-shunt device by the diagrams of frequency, step and impulse responses and also stability diagrams that verify the best configurations for the machining process.