Vibration Reduction of Flexible Beams using Shape Memory Alloys

Damage to machinery due to large vibration amplitudes at or near critical speeds can be avoided by the use of external dampers, which help in keeping vibration amplitudes under tolerable limits by dissipating- a -p art of the undesirable vibration energy generated. Of several mechanisms by which external dampers could be provided, application of shape memory alloys (SMA) for the purpose was recently started gaining attention from researchers. As such an attempt has been made to explore the possibility of applying SMA for vibration attenuation. Systematic experiments have been carried out in order to study the feasibility of using an SMA strip to reduce the vibration of a typical structural element like a cantilever beam. The performance of the SMA strip in this context has been defined qualitatively in the form of decay curves and quantitatively in terms of the damping ratio. The study has very clearly indicated that an SMA strip is a potential candidate when applied as a layered damper in flexible structures. The study also indicates that the application of an SMA strip needs to be optimized for better performance and the possibility of realizing active vibration contro