Case Study 1.1: Identification and Active Damping of Critical Workpiece Vibrations in Milling of Thin Walled Workpieces

Abstract

In milling of impellers and blisks (blade integrated disks), critical workpiece vibrations of thin-walled blade structures occur due to the excitation by the process forces and the dynamic compliance of the sensitive elements of the parts. Workpiece vibrations lead to inacceptable effects on the blade surfaces and thus to the production of defective parts. Also, these vibrations provoke an increased tool wear progress. Within the INTEFIX project, fixture solutions were developed which enable the detection and compensation of chatter vibrations during machining of thin-walled workpiece elements. This contribution introduces the development of an intelligent chuck for the clamping of impellers. The chuck exploits CFRP embedded piezo patch transducers for the identification of critical workpiece vibrations during milling. By means of an integrated piezo actuator, counter vibrations can be applied which disturb the regenerative chatter effect and lead to a decreased waviness of the workpiece surface. The development of the mechatronic clamping system is supported by innovative process simulation approaches.