Accession Number:

AD0759507

Title:

Melt-Grown Oxide-Metal Composites

Descriptive Note:

Semi-Annual rept. no. 5, 10 Jun-9 Dec 1972

Corporate Author:

GEORGIA INST OF TECH ATLANTA SCHOOL OF CERAMIC ENGINEERING

Personal Author(s):

• Chapman, Alan T.
• Benzel, James F.
• Cochran, J. K.
• Feeney, Robert K.
• Long, F. W.

Report Date:

1973-01-01

Pagination or Media Count:

114.0

Abstract:

This research is designed to develop melt-grown oxide-metal composite structures for high field electron emission testing. A number of refractory oxide-metal mixtures i.e. UO2-W, stabilized ZrO2 and HfO2-W, UO2-Ta, and the rare earth oxides of Gd2O3, Nd2O3 and La2O3-Mo and W have been successfully induction melted and unidirectionally solidified to form aligned metallic fibers embedded in the oxide matrix. The system CeO2-Mo was added to this list this report period. The chemical etching behavior of UO2-W and CeO2 doped Gd2O3-Mo samples was extensively studied to establish conditions for forming a variety of desirable emitter configurations. Experimental electron emission testing has progressed through the use of better samples and improved etching and brazing procedures to the point where bulk emission currents of several hundred mAsq cm can be routinely obtained. A three-dimensional numerical approximation is being used to theoretically analyze the field emission performance of various pin array geometries.

Descriptors:

• *CERAMIC MATERIALS
• *COMPOSITE MATERIALS
• *CRYSTAL GROWTH
• *EUTECTICS
• *FIELD EMISSION
• *REINFORCING MATERIALS
• DIODES
• FIBERS
• FREEZING
• HAFNIUM COMPOUNDS
• MELTING
• MOLYBDENUM
• OXIDES
• RARE EARTH ELEMENTS
• TUNGSTEN
• URANIUM COMPOUNDS
• ZIRCONIUM OXIDES

Subject Categories:

• Ceramics, Refractories and Glass
• Laminates and Composite Materials
• Electricity and Magnetism

Distribution Statement:

APPROVED FOR PUBLIC RELEASE