Posted: July 30, 2009

Researchers discover ultra damping in shape-memory alloys

(Nanowerk News) A joint research team from the University of the Basque Country and the United States MIT (Massachusetts Institute of Technology), led by Professor of Physical Metallurgy, Mr José María San Juan, has shown that copper, aluminium and nickel alloys with shape memory have a much higher damping index in nano sizes than in macroscopic dimensions. In a few milliseconds, these alloys acquire excellent properties given their “ultrahigh damping” that makes them ideal materials for eliminating nano-scale vibrations or impacts in sensors and detectors.
The findings have been published in Nature Nanotechnology ("Nanoscale shape-memory alloys for ultrahigh mechanical damping").
The practical application of this feature will enable the development of much more precise and hard-wearing ABS brakes in the field of transport or, in the domestic field, washing machines with a quieter and more stable centrifuging. It will also be possible to create more sensitive microsensors and micro devices for use in biomedicine, aeronautics or robotics - disciplines where alloys of materials with shape memory are of great importance.
Alloys with shape memory are able to recover their initial shape after being subjected to changes in temperature. In this process, configured by two phases called Austenite and Martensite, the materials with shape memory can dissipate large quantities of mechanical energy, this being responsible for the damping properties.
Source: Basque Research