Case study 1.1: Identification and active damping of critical workpiece vibrations in milling of thin walled impellers/blisks

Demonstrator overview

The “i-chuck” will be a fixture for machining of blisks and impellers with thin-walled blades which tend to vibrate during the process. The aim is to provide integrated sensor and actuator technology to observe and avoid unstable process conditions.
During machining of impellers, vibrations of the thin-walled blades occur due to their low stiffness and the excitation by the tool engagement.These vibrations can lead to unstable process conditions which cause unacceptable surface quality and higher tool wear. The first goal is to detect such unstable conditions with fixture-integrated sensors. Secondly, an active counter action to reduce workpiece vibrations and to avoid process instability shall be achieved with suitable actuators inside the fixture.

Description of the infrastructure

Industrial production envirnoment for small batch and single piece production, job shop production.

Detailed description of the demonstrator

The demonstrator will consist of a new clamping chuck for impellers and blisks which integrates sensors for workpiece vibration detection and identification of unstable process conditions, and actuators to counteract critical vibrations.
The regarded test-impeller is made of EN AW-7075 and will be machined by simultaneous 5-axes milling.