Surface and grain boundary segregation of sulfur and boron in nickel

Journal Article · Tue Mar 01 04:00:00 EST 1988 · Acta Metall.; (United States)

DOI:https://doi.org/10.1016/0001-6160(88)90108-3· OSTI ID:6976547

Ladna, B; Birnbaum, H K

Auger electron spectroscopy and secondary-ion-mass spectrometry was used to study surface and grain boundary segregation of B and S in Ni. Sulfur segregation was not influenced by the presence of boron and resulted in a uniform monolayer surface and grain boundary coverage. Segregation of boron differed from that of sulfur and resulted in the precipitation of Ni/sub 3/B in the near surface layer. Borides dissolved into the matrix at temperatures above 923 K and precipitated during cooling. This process did not affect the segregation of sulfur, which covered the borides and matrix uniformly. Grain boundary segregation of boron, its effect on the co-segregation of sulfur and the tendency for intergranular fracture were studied using hydrogen charged fractured samples. Addition of boron reduced the tendency for intergranular fracture. A small amount of boron was found at the grain boundaries, together with sulfur and carbon; the sulfur and carbon levels were about 20% smaller than in the boron-free sample. The results suggest that boron has a beneficial effect on the strength of the grain boundaries and also reduces the negative effect of sulfur segregation.

• Research Organization: Dept. of Materials Science and Engineering, Univ. of Illinois at Urbana-Champaign, 1304 W. Green Street, Urbana, IL (US)
• OSTI ID: 6976547
• Journal Information: Acta Metall.; (United States), Journal Name: Acta Metall.; (United States) Vol. 36:3; ISSN AMETA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
360104 -- Metals & Alloys-- Physical Properties
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400800 -- Combustion
Pyrolysis
& High-Temperature Chemistry
656002 -- Condensed Matter Physics-- General Techniques in Condensed Matter-- (1987-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALLOYS
AUGER ELECTRON SPECTROSCOPY
BORON
BORON ADDITIONS
BORON ALLOYS
CARBON
COOLING
CRYSTAL STRUCTURE
ELECTRON SPECTROSCOPY
ELEMENTS
EVALUATION
FAILURES
FRACTURES
GRAIN BOUNDARIES
MASS SPECTROSCOPY
MATRICES
METALS
MICROSTRUCTURE
NICKEL
NONMETALS
PLASMA
PRECIPITATION
RESONANCE IONIZATION MASS SPECTROSCOPY
SEMIMETALS
SEPARATION PROCESSES
SOLID-STATE PLASMA
SPECTROSCOPY
SULFUR
SURFACE PROPERTIES
TECHNOLOGY ASSESSMENT
TEMPERATURE EFFECTS
THERMAL FRACTURES
TRANSITION ELEMENTS