Accession Number : ADA321521

Title :   Crystal Chemistry of Ceramic/Metal Systems.

Descriptive Note : Final rept. 29 Sep 92-13 Dec 96,

Corporate Author : NORTH CAROLINA UNIV AT CHAPEL HILL DEPT OF GEOLOGY

Personal Author(s) : Reeber, Robert R.

PDF Url : ADA321521

Report Date : 16 JAN 1997

Pagination or Media Count : 9

Abstract : Robust models for predicting high temperature/pressure thermal expansion for a range of solids have been developed. The inter-relationships between several thermophysical properties including thermal expansion, specific heat, elastic properties, and self-diffusion of materials has been investigated. The role of defects on thermal expansion at high temperature and pressure has also been explored. During the course of the project several models for thermal expansion were developed extending earlier work of Reeber. The product of thermal expansion, bulk modulus, and volume has been shown to approach a constant at high temperatures for alkali halides, rare earth oxides, fcc metals, and ZnS. Models have been applied to investigate high temperature thermal expansion of alkali halides, rare earth oxides, group IV elements, fcc metals, bcc metals, SiC, III-V and II-VI compounds. Analytical expressions have been provided that represent the thermal expansion of these materials from near 0 K to the melting point. Models have also been extended to high pressure thermal expansion of MgO, NaCl, Group IV elements, and W. The bulk modulus and self-diffusion for W and Ta have been predicted to their melting points.

Descriptors :   *METALS, *CERAMIC MATERIALS, *CRYSTAL CHEMISTRY, HIGH TEMPERATURE, ELASTIC PROPERTIES, ZINC SULFIDES, HIGH PRESSURE, SOLIDS, DEFECTS(MATERIALS), OXIDES, MATHEMATICAL ANALYSIS, THERMAL EXPANSION, HALIDES, GROUP III COMPOUNDS, GROUP IV COMPOUNDS, DIFFUSION COEFFICIENT, SODIUM CHLORIDE, RARE EARTH COMPOUNDS, TANTALUM, MELTING POINT, SILICON CARBIDES, TUNGSTEN, GROUP II-VI COMPOUNDS, SPECIFIC HEAT, MAGNESIUM OXIDES, ALKALI METAL COMPOUNDS, THERMOPHYSICAL PROPERTIES, BULK MODULUS.

Subject Categories : Inorganic Chemistry
      Physical Chemistry
      Crystallography
      Ceramics, Refractories and Glass

Distribution Statement : APPROVED FOR PUBLIC RELEASE