Accession Number:

ADA128941

Title:

Magnetoferroelectrics, Divertable Ferroelectrics and Pyroelectric Glass Ceramics.

Descriptive Note:

Final rept. 1 Jul 79-28 Feb 83,

Corporate Author:

PENNSYLVANIA STATE UNIV UNIVERSITY PARK MATERIALS RESEARCH LAB

Report Date:

1983-02-28

Pagination or Media Count:

94.0

Abstract:

During the past three years the major topics on which work was carried out under the above contract are grain oriented glass-ceramics for piezoelectric and pyroelectric devices shape memory effect in PLZT ceramics, and magnetoferroelectric effect. Several glass-ceramic compositions were developed which showed a high figure of merit for application in pyroelectric devices. They are also good candidate materials for piezoelectric resonators, and surface acoustic wave devices. In the report, the compositions, processing methods and advantages of glass-ceramics over single crystals for use in devices are classified at length. A connectivity model was developed for the prediction of piezoelectric and pyroelectric properties of multicomponent glass-ceramics. Shape-memory effect in metals and alloys is a well known phenomenon. It is the recovery of a plastically deformed material to its original shape by heating. Under the above program, shape-memory effect in PLZT ceramics was investigated. Another highlight of the past three years was the discovery of a new class of ferroelectric materials possessing a magnetically induced ferroelectricity called magnetoferroelectricity. A magnetoferroelectric develops a reversible spontaneous electric polarization on passing through a magnetic phase transition. The effect was demonstrated in chromium chrysoberyl Cr2Be04. Author

Subject Categories:

  • Ceramics, Refractories and Glass
  • Crystallography
  • Electricity and Magnetism

Distribution Statement:

APPROVED FOR PUBLIC RELEASE