Oxidation and reduction of Ni--Cr alloys

Journal Article · Mon Mar 01 04:00:00 EST 1982 · J. Vac. Sci. Technol.; (United States)

DOI:https://doi.org/10.1116/1.571465· OSTI ID:5533668

Smith, K L; Schmidt, L D

The oxidation and subsequent reduction of Ni--20 Cr was studied by scanning Auger microanalysis and x-ray photoelectron spectroscopy (XPS) with argon ion sputter profiling. Oxidation at 800 /sup 0/C produced a 5000 A layer of NiO over a 4000 A layer of primarily Cr/sub 2/O/sub 3/ on the alloy grain faces. Near the alloy grain boundaries a band of Cr/sub 2/O/sub 3/ formed which was 10 000 A wide and 2000 A thick. The rate of reduction of the oxide films was found to depend on the H/sub 2/ pressure. After 2 h at 500 /sup 0/C and 0.02 Torr of H/sub 2/ a <100 A Ni metal film formed over the NiO while at 1 atm of H/sub 2/ the NiO layer was completely reduced to Ni metal. The surface and subscale layers of Cr/sub 2/O/sub 3/ were not reduced under either condition.

• Research Organization: Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455
• OSTI ID: 5533668
• Journal Information: J. Vac. Sci. Technol.; (United States), Journal Name: J. Vac. Sci. Technol.; (United States) Vol. 20:3; ISSN JVSTA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360105* -- Metals &amp; Alloys-- Corrosion &amp; Erosion
ALLOYS
ARGON IONS
AUGER ELECTRON SPECTROSCOPY
BINDING ENERGY
CHALCOGENIDES
CHARGED PARTICLES
CHEMICAL ANALYSIS
CHEMICAL REACTIONS
CHROMIUM ALLOYS
CHROMIUM COMPOUNDS
CHROMIUM OXIDES
CRYSTAL STRUCTURE
ELECTRON SPECTROSCOPY
ELEMENTS
ENERGY
FILMS
GRAIN BOUNDARIES
HIGH TEMPERATURE
HYDROGEN
IONS
LAYERS
MICROSTRUCTURE
NICKEL ALLOYS
NICKEL BASE ALLOYS
NICKEL COMPOUNDS
NICKEL OXIDES
NONDESTRUCTIVE ANALYSIS
NONMETALS
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PHOTOELECTRON SPECTROSCOPY
REDUCTION
SPECTROSCOPY
SURFACE PROPERTIES
SURFACE TREATMENTS
TRANSITION ELEMENT COMPOUNDS
X-RAY EMISSION ANALYSIS