Accession Number : AD0270178

Title :   AN INVESTIGATION OF THE THEORETICAL AND PRACTICAL ASPECTS OF THE THERMAL EXPANSION OF CERAMIC MATERIALS

Corporate Author : CORNELL AERONAUTICAL LAB INC BUFFALO N Y

Personal Author(s) : SCHEETZ,HOWARD

Report Date : 30 NOV 1961

Pagination or Media Count : 1

Abstract : Extrapolation of elastic moduli data for porous ceramic bodies (for porosities of 5% or less) leads to values for the fully-dense body which lie between those computed by space averaging of single-crystal elastic stiffness and compliance constants. The elastic properties of composite bodies, including multiple-phase ceramics, may be predicted (with small error for bodies which remain continuous solids) by a method developed by Kerner. The elastic moduli which should be used for ceramics corresponds to the values for the fully-dense polycrystalline body rather than the lower values associated with the more readily available porous ceramics. The validity of Kerner's method for prediction of thermal expansion for multiple-phase ceramics was clearly shown for three different two-phase systems. (Author)

Descriptors :   *CERAMIC MATERIALS, *SPINEL, *THERMAL EXPANSION, ALUMINUM, ALUMINUM COMPOUNDS, COMPOSITE MATERIALS, GLASS, HIGH TEMPERATURE, MAGNESIUM COMPOUNDS, MATHEMATICAL ANALYSIS, MECHANICAL PROPERTIES, MIXTURES, OXIDES, POROUS MATERIALS, REFRACTORY MATERIALS, SILICON COMPOUNDS, THEORY, ULTRASONIC RADIATION

Distribution Statement : APPROVED FOR PUBLIC RELEASE