AVS 46th International Symposium
    Vacuum Technology Division Tuesday Sessions
       Session VT-TuP

Paper VT-TuP11
Study of Microgeometry of Activated Coals and Non-evaporable Getters

Tuesday, October 26, 1999, 5:30 pm, Room 4C

Session: Poster Session
Presenter: G.L. Saksaganski, The Efremov Research Institute of Electrophysica Apparatus, Russia
Authors: S.B. Nesterov, Moscow Power Engineering Institute, Russia
Yu.K. Vassiliev, Moscow Power Engineering Institute, Russia
G.L. Saksaganski, The Efremov Research Institute of Electrophysica Apparatus, Russia
Correspondent: Click to Email
Determination of the pumping speed is of crucial importance by design of the surface action pumps. Pumping speed depends on the sticking coefficient value. Dependence of the integral sticking coefficient for the whole cryopanel on the local sticking coefficient in the concrete point is being determined in this paper. Real surface of the sorbent is not flat. So a molecule of the pumped gas can be reflected from this surface several times. The real surface of different sorbents - activated coals and non-evaporable getters is analysed by scanning tunnel microscope. To calculate dependence of the cryopanel integral sticking coefficient on the local sticking coefficient on the sorbent surface the test particle Monte-Carlo method is used considering the real surface of a sorbent. Integral coefficient values obtained during the experiment allow one to compute the local coefficient value for the concrete sorbent type. Obtained results for various types of sorbents may be useful for engineers constructors of surface action pumps.