ATTAINMENT OF 10$sup -9$ mm Hg PRESSURE IN UNBAKED VACUUM SYSTEMS BY MOLYBDENUM EVAPORATION
The deposition of molybdenum by vaporization from simple hairpin filaments was found to reduce the pressure in an unbaked, stainless steel vacuura system to 4 x 10/sup -10/ mm Hg. The deposit of 300 milligrams from a single filament 0.050 inch in diameter and about 6 inches long, has maintained an 85- liter volume at a pressure below 10/sup -9/ mm Hg for a period of over 40 hours. A small, well-trapped diffusion pump is attached to the system to attain the initial pressure of 10/sup -7/ mm Hg and to pump the ungettered components which are presuraably responsible for the ultimate pressure in the system. The geometrical area of the molybdenum substrate was 8 x 10/sup 3/ cm/sup 2/. The initial pumping speed of this deposit was 4 x 10/sup 4/ liters per second for hydrogen. (auth)
- Research Organization:
- California. Univ., Livermore. Lawrence Radiation Lab
- DOE Contract Number:
- W-7405-ENG-48
- NSA Number:
- NSA-14-016744
- OSTI ID:
- 4136103
- Report Number(s):
- UCRL-5889
- Country of Publication:
- United States
- Language:
- English
Similar Records
THE EVAPORATION OF MOLYBDENUM IN THE PRESENCE OF CESIUM VAPOR
USE OF THE EVAPOR-ION PUMP WITH THE LINEAR ACCELERATOR