Nature of indigenous sulfur segregated to the free metal surface and to the scale-metal interface

Journal Article · Mon Feb 01 00:00:00 EST 1988 · Oxidation of Metals; (USA)

DOI:https://doi.org/10.1007/BF00656351· OSTI ID:5575698

Smeggil, J G; Peterson, G G ^[1]

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1. United Technologies Research Center, Hartford, CT (USA)

Sulfur segregation to the free metal surface of a Ni-20(wt.%)Cr-12(wt.%)Al alloy has been documented by high-temperature scanning Auger electron microscopy. Preferential enrichment of sulfur occurs to the surface of the chromium-rich {gamma} phase in the two-phase {gamma} nickel-{beta} (NiAl) alloy. Electron spectroscopy for chemical analysis (ESCA) studies have indicated that for a free metal surface, i.e., metal without an overlying thermally grown oxide scale, the surface segregated sulfur correlated with both S{sup {minus}2} and elemental sulfur. Energy-dispersive X-ray analysis (EDAX) characterization of fractured oxide films thermally grown on the Ni-Cr-Al alloy indicated that both a labile, i.e., relatively volatile, and a refractory sulfur species exist at the scale-metal interface. Elemental sulfur as detected by ESCA has the volatility characteristics found for the labile sulfur species found in the scanning electron microscopy (SEM)-EDAX studies.

• OSTI ID: 5575698
• Journal Information: Oxidation of Metals; (USA), Vol. 29:1-2; ISSN 0030-770X
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
OXIDATION
CHROMIUM ALLOYS
NICKEL BASE ALLOYS
PROTECTIVE COATINGS
ADHESION
SULFUR
SEGREGATION
AUGER EFFECT
ELECTRON SPECTROSCOPY
METALLURGICAL EFFECTS
OXIDES
SCALING
SCANNING ELECTRON MICROSCOPY
VOLATILITY
X-RAY DIFFRACTION
YTTRIUM
ALLOYS
CHALCOGENIDES
CHEMICAL REACTIONS
COATINGS
COHERENT SCATTERING
DIFFRACTION
ELECTRON MICROSCOPY
ELEMENTS
METALS
MICROSCOPY
NICKEL ALLOYS
NONMETALS
OXYGEN COMPOUNDS
SCATTERING
SPECTROSCOPY
TRANSITION ELEMENTS
360105* - Metals & Alloys- Corrosion & Erosion
360102 - Metals & Alloys- Structure & Phase Studies