Accession Number : AD0875143

Title :   Studies of Graphite Vaporization Using a Modulated Beam Mass Spectrometer.

Descriptive Note : Summary rept. 1 Feb 69-31 Jan 70,

Corporate Author : AVCO CORP LOWELL MA SYSTEMS DIV

Personal Author(s) : Steele, Warren C.

Report Date : MAR 1970

Pagination or Media Count : 43

Abstract : A set of experiments employing a mass spectrometer to study the kinetics and thermodynamics of graphite vaporization are described. Results from equilibrium vaporization studies which are comparable to accepted literature values were obtained by the Knudsen effusion technique. Comparative studies of free vaporization from polycrystalline graphite surfaces have demonstrated the effect of surface conditions, such as porosity, on this type of process. Highly porous surfaces were seen to give results very close to those of equilibrium vaporization. Special experiments on the reflection of carbon vapor by graphite surfaces were performed, and the variation in reflected beam intensity with surface temperature is given for C1, C2, and C3. Early results of reflection experiments using modulated carbon vapor beams are also described. (Author)

Descriptors :   *VAPORIZATION), (*GRAPHITE, (*MASS SPECTROSCOPY, GRAPHITE), CHEMICAL EQUILIBRIUM, SURFACE PROPERTIES, MOLECULAR BEAMS, THERMOCHEMISTRY.

Subject Categories : Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE