New elastomagnetic multilayers for the passive attenuation of vibrations, adaptable to external stimulation

Kurzfassung

An Italian sciences department developed a new elastomagnetic multilayer made of alternate layers of rigid plastic magnet and non-magnetic, elastic material has been produced and tested as a spontaneous vibration damper, so that it can be used in civil and mechanical structures. The new material becomes stiff with the compressive deformation magnitude and distorts the harmonic oscillations. Partners for different tests in laboratories and for further applying to industrial cases are sought.

Details

Vibration control is a very important issue in the field of civil engineering, automotive, naval and aeronautic industries, with regard to travel comfort, industry manufacturing mechanical components that are submitted to oscillatory stimulations, etc. Different devices for vibration attenuation have been developed, working as passive dissipators or active controllers.
The new conceived elastomagnetic composite is developed for applications as vibration damper. It can work fundamentally as a passive vibration attenuator, able, moreover, to adapt its response to the dynamic vibration amplitude to be damped.
The new elastomagnetic composite increases rigidity with the compressive strain increase, it is able to change significantly the spontaneous vibration frequency of the vibrating structure under control (with about 15%) and to attenuate the structure vibration amplitude (45% attenuation of the initial vibration amplitude). The novel elastomagnetic composite represents a promising passive element, with auto-adaptive properties, for vibration attenuation.

Innovative Aspects:
The ability to adjust the material response to the external vibration magnitude without requiring an auxiliary device for control and activation makes the elastomagnetic composite innovative with respect to the standard passive vibration attenuators.
The active composite material can assume the desired shape for all the peculiar application conditions.
With comparison to the standard passive attenuators, the elastomagnetic multilayer damper exhibits some peculiar properties:
a. Increasing rigidity with compressive deformation.
b. Ability to induce a significant shift in the spontaneous vibration frequency of the structure under control.

An attenuator made with a core based on the novel elastomagnetic composite should have about the same cost as the passive attenuators already on the market while exhibiting improved performances and higher adaptability to surrounding conditions (corrosive ambient, biological ambient, shape requirements, etc.).