Accession Number : ADA293556

Title :   Poisson's Ratio for Hexagonal Crystals.

Descriptive Note : Technical rept.,

Corporate Author : ARMY RESEARCH LAB FORT MONMOUTH NJ

Personal Author(s) : Ballato, Arthur

PDF Url : ADA293556

Report Date : MAR 1995

Pagination or Media Count : 13

Abstract : General expressions for Poisson's ratio are derived for hexagonal crystals; simplified forms are given for cases involving symmetry directions. Crystals of hexagonal symmetry include a number of the binary semiconductor systems with the piezoelectric wurtzite structure, such as GaN and AlN. These are becoming increasingly important for high technology applications. One of the most important representatives of this class is the family of poled electroceramics, including BaTiO3, PZT, and related alloys. All hexagonal classes have the same elastic matrix scheme, so for our purposes it is not necessary to distinguish between the different point groups; the presence of piezoelectricity is neglected. jg

Descriptors :   *CRYSTALS, *POISSON RATIO, STRUCTURES, ZINC SULFIDES, SEMICONDUCTORS, ALLOYS, CERAMIC MATERIALS, SYMMETRY, PIEZOELECTRIC MATERIALS, BARIUM, TITANATES, ZIRCONATES, LEAD(METAL), BINARY COMPOUNDS.

Subject Categories : Crystallography
      Ceramics, Refractories and Glass
      Properties of Metals and Alloys
      Quantum Theory and Relativity
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE