SMART STRUCTURES 

AND MATERIALS 



The above laminate is a typical adaptive
composite, possessing outer layers of the piezoelectric barium titanate
and an inner core of the magnetostrictive cobalt ferrite. The composite
responds to both electric and magnetic field through a product property
quantified by the constitutive laws of the two constituent materials in
the composite. With its specific color scheme and unique coupled properties,
this material is known as a ``Raminate''. 

Electric displacement and magnetic flux are
two of the secondary variables (along with elastic stress) that allow us to
quantify the behavior of this class of composite. In this figure, the throughthickness
component of the magnetic flux vector is shown for a 2layer hybrid laminate
under applied surface magnetic potential. The top layer is not magnetostrictive,
and hence has a very simple linear behavior through the thickness. The lower
layer of cobalt ferrite has a much stronger nonlinear response behavior. Shown
here is the exact solution comapred with a discretelayer model using a varying
number of mathematical layers to describe the laminate fields. 
