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Secondary electron emission characteristics of untreated and ion-textured titanium
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Jensen, Kenneth A. Blackford, Gary A. Curren, Arthur N. |
| Copyright Year | 1989 |
| Description | Experimentally determined values of true secondary electron emission and relative values of reflected primary electron yield are presented for untreated (simply machined) and ion-textured, high-purity titanium over ranges of primary electron beam energies and beam impingement angles. The purpose of the investigation was to explore the feasibility of using titanium as electrode material in the multistage depressed collectors (MDC's) used in microwave amplifier traveling wave tubes (TWT's) for space communications and aircraft applications. Because of its relatively low density and thermal expansion characteristics and relatively high strength, thermal emissivity, and melting temperature, titanium presents itself as a possible candidate for the MDC electrode application. A detailed description of the method of ion texturing the titanium is included. Although the ion-treated surface considered in this study is not presented as being optimum from the standpoint of secondary electron emission suppression, it nevertheless serves to demonstrate that the surface can be modified by this procedure to significantly reduce these emission characteristics relative to those of the untreated surface. Further studies can reasonably be expected to produce surfaces with even lower secondary emission characteristics. The titanium surface were tested at primary electron beam energies of 200 to 2000 eV and at direct (0 deg) to near-grazing (85 deg) beam impingement angles. True secondary electron emission and relative reflected primary electron yield characteristics of the surfaces were compared with each other and with textured titanium surface exhibited secondary electron emission characteristics sharply lower than those exhibited by untreated titanium or copper. Clearly, then, in consideration of the secondary electron emission suppression of ion-textured titanium along with its other favorable physical properties, it must be included as a potential candidate for use as MDC electrode material in some applications. |
| File Size | 7568911 |
| Page Count | 15 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19890008279 |
| Archival Resource Key | ark:/13960/t71w0dp79 |
| Language | English |
| Publisher Date | 1989-03-01 |
| Access Restriction | Open |
| Subject Keyword | Metallic Materials Tantalum Traveling Wave Tubes Ion Plating Machining Titanium Electron Emission Secondary Emission Surface Finishing Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
