Abstract
Honeycombs are in widespread use as cores for sandwich structures. Auxetic materials
(materials with a negative Poisson’s ratio) expand laterally when stretched. In this paper
we consider auxetic honeycomb cores consisting of chiral units of cylinders and
tangentially attached ribs. The use of these cylinders and ribs allows the decoupling of
the shear stiffness and compressive strength, with the ribs providing the shear stiffness
and the cylinders the compressive buckling resistance. Auxetic structures are proposed
because they display high in-plane shear stiffness and synclastic curvature, that is, they
form domes rather than saddle structures, making them ideal for consideration as next
generation sandwich cores.
Furthermore, we have embedded a piezo ceramic transducer (PZT) inside the wall of an
auxetic chiral honeycomb structure. The piezo ceramic transducer can be used in either
active or passive modes providing increased functionality to the core as either an actuator
promoting in plane or out of plane shape changes or as a sensor for structural health
monitoring (SHM). SHM can be achieved either through direct measurement of
deformations inside the honeycomb or via NDA type vibrational structural interrogation.
In this paper we demonstrate manufacture of auxetic chiral honeycombs with embedded
PZTs and show how a PZT transducer can be used to actively drive the deformation of
the structure and to detect applied deformations and vibrations. Finite element modelling
simulating this experimental work is used to optimise the location of the patch within the
structure and for further development of the whole system.
Translated title of the contribution | Multifunctional Negative Poisson’s ratio (Auxetic) Honeycomb Cores with Embedded Piezo-ceramic Patches |
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Original language | English |
Title of host publication | Proceedings of ECCM-13, June 2-5, Stockholm, Sweden |
Publication status | Published - 2008 |
Bibliographical note
Name and Venue of Event: ECCM-13Conference Organiser: ESCM