EVALUATION OF MACHINABLE, ACID-TREATED, RECONSTITUTED ALUMINA FOR ELECTRON TUBES.
Abstract
A constant problem involved in the use of ceramic components in experimental tube development work is the acquisition of the required ceramic piece parts in minimum time and at minimal cost to the project. A method to soften high-purity polycrystalline alumina for machining purposes and then reconstituting (redensifying) the machined ceramic to a dense state has been developed. Samples of acid-treated, machined, reconstituted alumina (96% Al2O3) ceramic were obtained and evaluated for possible use in the electron tube work. Tests were conducted to determine: (1) effects on the emission characteristics of a dispenser cathode when acid-treated, reconstituted ceramics were positioned in the vacuum tube envelope near an operating cathode; (2) the capability of the ceramic to be metalized and brazed into vacuumtight assemblies; and (3) tensile strength of the resulting seals. The test results obtained on the limited number of acid-treated, reconstituted samples available indicate that the acid-treated, reconstituted alumina (96% Al2O3) can be metalized, brazed, and included within the electron tube vacuum envelope without any deleterious effects on tube performance. However, further test data will have to be obtained on the hermeticity of the seals made with acid-treated, reconstituted ceramic before any valid conclusions can be given on the use of these ceramics for high-vacuum applications. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1967
- Accession Number
- AD0651930
Entities
People
- Stanley R. Dubuske
- Stanley R. Leefe
Organizations
- United States Army Communications-Electronics Command