Continued Development and Testing of Tungsten Controlled Porosity Dispenser Cathodes.

摘要

The objective of this effort was to continue the development and testing of Tungsten CPD Cathodes. The results of the effort were to produce cathodes with emission levels approximately equivalent or better than those of standard metal matrix B-type cathodes but with the demonstrated advantages of uniform emission and long life. The use of chemical vapor deposition (CVD) has been successfully demonstrated, and units are currently under life test. Laser drilling techniques have been developed so that planar and spherically contoured cathode surfaces can be produced. Although laser drilling may not be perfect, it is the most expedient technique and the only one proven to be able to produce the objectives of 5 micron holes on 15 micron centers in 25 micron thick tungsten. All cathodes placed on life test in this and the prior contract will be continued on life test per contract requirements.