Studies of chromium gettering

Conference · Fri Jan 01 04:00:00 EST 1982

OSTI ID:5843435

Simpkins, J E; Mioduszewski, P; Stratton, L W

Preliminary results have shown that hydrogen pumping by chromium is a surface effect. Unlike with titanium, the getter material used in many present day tokamaks, there is no significant diffusion into the bulk. Additional experiments have been carried out to measure the basic characteristics of chromium films for gases of interest in tokamak research. These gases include deuterium, oxygen and nitrogen. A vacuum system is described which allowed precise control of the test gas, a constant wall temperature and determination of the projected getter surface area. A quadrupole mass spectrometer, rather than simply a total pressure gauge, was utilized to measure the partial pressure of the test gas as well as the residual gas composition in the system. A quartz crystal monitor was used to measure film thickness. Pumping speeds and sticking coefficients are given as a function of surface coverage for each test gas. A comparison will be made with titanium films deposited in the same vacuum system and under similar conditions.

• Research Organization: Oak Ridge National Lab., TN (USA)
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 5843435
• Report Number(s): CONF-820545-24; ON: DE83017186
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700209* -- Fusion Power Plant Technology-- Component Development & Materials Testing
CHROMIUM
CLOSED PLASMA DEVICES
DEUTERIUM
ELEMENTS
GETTERS
HYDROGEN ISOTOPES
ISOTOPES
LIGHT NUCLEI
METALS
NITROGEN
NONMETALS
NUCLEI
ODD-ODD NUCLEI
OXYGEN
PERFORMANCE TESTING
STABLE ISOTOPES
TESTING
THERMONUCLEAR DEVICES
TITANIUM
TOKAMAK DEVICES
TRANSITION ELEMENTS