I saw an article recently about structures that shrink when pulled instead of stretching. I don't know how or if it is OK to link articles but I was wondering if these could be used to damp cabinets or turntables?
As written you seem to be describing something unstable. If you pull on the material and it moves in the opposite direction then whatever is doing the pulling is likely to pull harder (e.g. a stretched spring), the material then shrinks more, the pull is even stronger, etc... until something breaks or the source of energy within the material doing the work is exhausted (e.g. a phase change).
Damping is a force that opposes motion, transferring mechanical energy to internal energy (heat), whereas what you seem to be describing is doing the opposite and reinforcing motion. A link or fuller description is needed to see if what is being described is part of a perpetual motion machine, is local to a region of the material but not overall, the internal energy of the material is changed requiring work to be put in to return to the starting conditions, etc...
I've found this, and see a mention of vibration damping of buildings: https://scitke.com/watch-new-structures-shrink-instead-of-stretching-when-pulled/#:~:text=Researchers in the Netherlands have developed innovative mechanical,snap inward — rather than expand when pulled.
Researchers in the Netherlands have created mechanical structures that strangely shrink – or more precisely, snap inward – instead of stretching outward when pulled.
Researchers in the Netherlands have created mechanical structures that strangely shrink – or more precisely, snap inward – instead of stretching outward when pulled.
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That is the thing I saw, didn't read into it but saw the part about vibration damping qualities so it got me wondering
I can see (a very complicated) way to avoid driving resonances in a particular frequency range which could be useful in some circumstances. This involves changing stiffness and inertia but won't dissipate energy. If you add damping to a nonlinear mechanism it tends to "pump up" and progressively stiffen reducing deflection (e.g. off-road bikes with non-linear swing arms and linear dampers). It might be possible to do something with active damping but that would be piling complexity on top of complexity. If the complexity approaches that of active control then it becomes pointless because a reasonable active control system is almost certainly going to out perform any passive one.