Accession Number : AD0248983

Title :   A COMPARISON OF OXYGEN ON TUNGSTEN AND MOLYBDENUM BY FIELD ELECTRON MICROSCOPY

Corporate Author : NOTRE DAME UNIV IN

Personal Author(s) : MORGAN, D.R. ; COOMES, E.A.

Report Date : 21 SEP 1960

Pagination or Media Count : 1

Abstract : A STUDY WAS MADE OF THE BEHAVIOR OF O ON W AND MO BY FIELD EMISSION MICROSCOPY (FEM) FROM 1000 TO 1900 DEGREES K) THE CHANGES IN THE FEM PATTERNS WERE STUDIED AS A FUNCTION OF O COVERAGE AND AS A FUNCTION OF TIME WITH ACTIVATION TEMPERATURE9 A COMPARISON WAS MADE OF UNSATURATED O COVERAGE ON W AND MO) ACTIVATION ENERGIES WERE CALCULATED FOR THE PATTERNS AT THE LOW, INTERNEDIATE, AND HIGH ACTIVATION TEMPERATURE RANGES. THE MOST MARKED VARIATION IN EMISSION PATTERNS OCCURRED IN THE LOW-TEMPERATURE RANGE. THESE CHANGES WERE ATTRIBUTED TO A REARRANGEMENT OF THE O-W AND O-MO COMPLEXES AND TO THE POSSIBLE FORMATIONOF A DIFFERENT OXIDE. THE PATTERNS FOR SATURATED COVERAGES APPARENTLY DID NOT CORRESPOND TO THE UNSATURATED EMITTER. STABLE STATES WERE OBTAINED IN THE LOW AND INTERNEDIATE TEMPERATURE RANGES. THE RESULTS APPEARED TO INDICATE THAT BOTH OXIDATION AND DESORPTION OCCUR AT THE TEMPERATURES USED. SIX OXIDES OF MO AND 5 OXIDES OF W WERE IDENTIFIED BY X-RAY ANALYSIS

Descriptors :   *ELECTRON MICROSCOPY, *FIELD EMISSION, *METAL FILMS, *MOLYBDENUM, *OXYGEN, *STRONTIUM COMPOUNDS, *TUNGSTEN, ADSORPTION, CHEMICAL REACTIONS, OXIDATION, OXIDES.

Distribution Statement : APPROVED FOR PUBLIC RELEASE