Accession Number : AD0277266

Title :   NEW METHOD FOR MEASURING SURFACE ENERGIES AND TORQUES OF SOLID SURFACES

Corporate Author : CARNEGIE INST OF TECH PITTSBURGH PA

Personal Author(s) : SHEWNON,P.G.

Report Date : APR 1962

Pagination or Media Count : 1

Abstract : A novel technique for determining the surface energy and its derivative with respect to orientation is described. Essentially it involves the floating of a wedge on the substrate, said wedge being made of a material which is not wet by the substrate, i.e., as a greased needle floats on water. A thermodynamic analysis of a system in which the wedge is supported entirely by surface energy is given. If the original surface is not at a cusp orientation, the surface tension is directly measurable from the groove angle formed. If the original surface is at a cusp orientation, there may or may not be a groove depending on the relative values of the derivative with respect to orientation and the weight of the wedge. Experiments primarily on Cu and Ag showed that sapphire, quartz and refractory metal wedges were wet while graphite wedges were not. The technique was demonstrated to work using graphite wedges, but the results obtained were not as accurate as those obtained by other workers using the wire-creep experiments. (Author)

Descriptors :   *SOLID STATE PHYSICS, *SURFACE PROPERTIES, *SURFACES, COPPER, ENERGY, GRAPHITE, HIGH TEMPERATURE, MEASUREMENT, METALS, SAPPHIRE, SILVER, SOLIDS, SURFACE ACTIVE SUBSTANCES, THEORY, THERMODYNAMICS

Distribution Statement : APPROVED FOR PUBLIC RELEASE