DYNAMICAL DEFORMATION SENSORS BASED ON THIN FERROELECTRIC PZT FILMS

The conditions of preparation of thin polycrystalline ferroelectric PZT films of Pb(Zr0.53Ti0.45W0.01Cd0.01)O-3 chemical constitution obtained by r.f sputtering are presented. Two variants of the technique are demonstrated, namely (1) sputtering of a powdered ceramic target in a continuous r.f. discharge and (2) sputtering of a hot-pressed target in a pulsed r.f, discharge. On the basis of thin films deposited on stainless steel, isotropic piezoelectric sensors of dynamical deformation have been constructed. The sensors have been calibrated in the range of low frequencies and their properties investigated under both laboratory and industrial conditions. On the basis of thin PZT-type films deposited on ceramic substrates (polycor), anisotropic piezoelectric sensors of dynamical deformation have been built. Investigations performed under laboratory conditions have shown that one can use such anisotropic sensors for measuring the main components of the deformation tenser of the surface of the sample under investigation and for determining the angle between the sensor axis and the main axis of the deformation tensor.