Accession Number : ADA265664


Title :   Ceramic Actuators for Smart Materials


Descriptive Note : Final rept. 1 Jul 1991-30 Jun 1992


Corporate Author : PENNSYLVANIA STATE UNIV UNIVERSITY PARK APPLIED RESEARCH LAB


Personal Author(s) : Cross, L E


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a265664.pdf


Report Date : Jun 1992


Pagination or Media Count : 66


Abstract : In earlier studies a number of phase switching systems had been explored which permit the switching of large electric polarization and the associated high elastic strain. The question to be resolved was whether these large polarization values could be repeatedly switched without associated mechanical or electrical fatigue. Early fatigue was shown to be an electrode problem and with care in electrode application, density control, grain size control and field homogeneity it was shown that full switching lifetimes with no fatigue of more than 10(exp 9) cycles were achievable. In polymer-ceramic composite transducers the 1:3 type connectivity is highly desirable. A new theoretical approach has been made to calculate die inhomogeneous stress profiles in both piezoceramic and polymer phases. The predictions have been tested using the MRL ultradilatometer and good agreement is shown between predicted and observed strain profiles. A new type of 1:3 composite making use of radially poled ceramic tubes has been explored and shown to offer unusually attractive possibilities for the control of piezoelectric, elastic and electric impedance characteristics and to offer a vehicle for the new electrostrictive agile piezoelectrics.


Descriptors :   *CERAMIC MATERIALS , *TRANSDUCERS , *ACTUATORS , CONTROL , DENSITY , POLARIZATION , PREDICTIONS , MATERIALS , POLYMERS , PROFILES , PIEZOELECTRIC MATERIALS , DILATOMETERS , TUBES , HOMOGENEITY , SWITCHING , IMPEDANCE , VEHICLES , FATIGUE , ELECTRODES , COMPOSITE MATERIALS , ELASTIC PROPERTIES , GRAIN SIZE , ELECTRIC FIELDS , STRAIN(MECHANICS) , PHASE


Subject Categories : Physical Chemistry
      Polymer Chemistry
      Electrical and Electronic Equipment
      Ceramics, Refractories and Glass


Distribution Statement : APPROVED FOR PUBLIC RELEASE