Restoration of piezoelectric effect in BaTiO/sub 3/ crystals

Piezoelectric materials are mainly used in devices for converting mechanical strain into an electrical signal and vice versa. Because of harsh environment, rough and long use most of the sensors are discarded. Their retrieval is not simple due to their design, delicacy of crystals and lack of know-how about technology of smart materials. Study has been carried out to restore piezoelectric properties of discarded crystals. The established process includes dismantling of piezo-crystals, silver electroding, poling and assembly of crystals. The poling and assembly results are characterized on the basis of impedance, tangent loss and admittance using LCR bridge and transducer analyzer. Mechanical requirements of crystal assembly are also discussed. The values of admittance of transducer were optimized by varying assembly pressure. (author)