Accession Number : AD0747267

Title :   Measurement of Interfacial Energies in Solid State Metals and Alloys.

Descriptive Note : Final technical rept. 1 Mar 69-30 Jun 72,

Corporate Author : UNIVERSITY OF SOUTHERN CALIFORNIA LOS ANGELES DEPT OF ELECTRICAL ENGINEERING

Personal Author(s) : Murr,Lawrence E.

Report Date : JUL 1972

Pagination or Media Count : 67

Abstract : The method of zero creep of small diameter 304 stainless steel wires coupled with scanning and transmission electron (shadowgraphic) microscopy of grain boundary-surface intersection grooves was used to measure average values for the surface free energy, F(S), and the grain boundary free energy, gamma(gb) at temperatures of 1060, 1160, 1260 and 1360C, from which the temperature coefficients of the specific interfacial free energies, were measured. Mean values of coherent twin boundary free energy/grain boundary free energy ratios were determined for low-torque twin-grain boundary intersections in thin foils of 304 stainless steel using techniques of transmission and diffraction electron microscopy. The techniques of transmission electron microscopy have been employed in a study of coherent annealing twins and their energetics in ultra-pure aluminum. The use of techniques developed for the measurement of interfacial free energies is expanded and discussed in connection with composite and dispersion-hardened systems. Particular emphasis on techniques of scanning electron microscopy are presented.

Descriptors :   (*METALS, SURFACE PROPERTIES), (*GRAIN BOUNDARIES, SURFACE PROPERTIES), INTERFACES, FREE ENERGY, ELECTRON DIFFRACTION, STAINLESS STEEL, GRAIN STRUCTURES(METALLURGY), ELECTRON MICROSCOPY, THORIUM COMPOUNDS, COMPOSITE MATERIALS, ALUMINUM, STAINLESS STEEL

Subject Categories : Metallurgy and Metallography
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE