The effect of diffusive hydrogen segregation on fracture of polycrystalline nickel

Journal Article · Tue Jul 01 00:00:00 EDT 1986 · Acta Metall.; (United States)

DOI:https://doi.org/10.1016/0001-6160(86)90010-6· OSTI ID:6965331

Lassila, D H; Birnbaum, H K

Hydrogen embrittlement was studied under conditions which allowed diffusion and segregation of hydrogen to grain boundaries to be controlled. Even at high solute concentrations of hydrogen, the fracture mode was ductile shear rupture if transport of hydrogen to grain boundaries was not allowed. As the amount of hydrogen segregation increased, the fracture mode became intergranular. Analysis of temperature dependence yields a hydrogen segregation enthalpy of 11.6KJ/mol. The transition was also observed at a constant aging temperature by increasing the solute hydrogen concentration. The kinetics suggest that the hydrogen segregation layer extends about 35 nm from the grain boundary. The fracture mechanism is a softening in region due to the high hydrogen concentration.

• Research Organization: NASA-Ames Research Center, Moffett Field, CA (US)
• OSTI ID: 6965331
• Journal Information: Acta Metall.; (United States), Journal Name: Acta Metall.; (United States) Vol. 34:7; ISSN AMETA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102 -- Metals & Alloys-- Structure & Phase Studies
360103* -- Metals & Alloys-- Mechanical Properties
AGING
CHEMICAL REACTION KINETICS
CRYSTAL STRUCTURE
CRYSTALS
DIFFUSION
DUCTILITY
ELEMENTS
EMBRITTLEMENT
ENTHALPY
FAILURES
FRACTURE MECHANICS
FRACTURES
GRAIN BOUNDARIES
HYDROGEN EMBRITTLEMENT
KINETICS
MECHANICAL PROPERTIES
MECHANICS
METALS
MICROSTRUCTURE
NICKEL
PHYSICAL PROPERTIES
POLYCRYSTALS
REACTION KINETICS
RUPTURES
SHEAR
SOLUTES
STRUCTURAL CHEMICAL ANALYSIS
TENSILE PROPERTIES
THERMAL DIFFUSION
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENTS