Accession Number : AD0608660


Title :   ANALYSIS OF METHODS FOR DETERMINING OUTGASSING RATES


Corporate Author : ARNOLD ENGINEERING DEVELOPMENT CENTER ARNOLD AFB TN


Personal Author(s) : Shipp, J I ; Trelinger, J D


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/608660.pdf


Report Date : Dec 1964


Pagination or Media Count : 31


Abstract : Methods of determining outgassing rates of materials under vacuum are discussed with emphasis on the accuracy and limitations of each. Pressure measurement techniques included are rate of evacuation, rate of rise, and a number of conductance methods. Assuming Langmuir's model for sticking probability, it is shown that these techniques can introduce large errors in determinations of desorption rates due to incorrect choice of pumping speed. Instrument calibration procedures and comparisons of results employing different techniques are also given.


Descriptors :   *DEGASIFICATION , *VACUUM PUMPS , ABSORPTION , ADSORPTION , CONDUCTIVITY , FLOWMETERS , GAS FLOW , GASES , IONIZATION GAGES , MASS SPECTROSCOPY , MATERIALS , MEASUREMENT , PRESSURE , SPECTRUM ANALYZERS , SUBLIMATION , VACUUM


Subject Categories : Industrial Chemistry and Chemical Processing
      Pumps, Filters, Pipes, Tubing, Fittings & Vlvs


Distribution Statement : APPROVED FOR PUBLIC RELEASE