Low temperature hydrogen embrittlement of niobium. II. Microscopic observations

Journal Article · Tue Feb 01 04:00:00 EST 1977 · Acta Metall.; (United States)

DOI:https://doi.org/10.1016/0001-6160(77)90117-1· OSTI ID:7317196

Grossbeck, M L; Birnbaum, H K

The detailed, microscopic processes which occur during the hydrogen embrittlement of pure Nb are examined using in situ SEM crack propagation studies, SEM fractography, electron diffraction and ion probe methods. These results show that the fracture process occurs in a stress induced NbH hydride phase which forms in front of the propagating crack. The experimental results are in good agreement with the stress induced hydride embrittlement mechanism which is discussed. The thermodynamics of precipitation of hydrides under external stress is discussed and calculations are presented for the stress effects on the ..cap alpha..-..beta.. solvus temperatures. These are related to the embrittlement process and evidence is presented to support the calculated stress effects on the solvus temperature.

• Research Organization: Univ. of Illinois, Urbana
• OSTI ID: 7317196
• Journal Information: Acta Metall.; (United States), Journal Name: Acta Metall.; (United States) Vol. 25:2; ISSN AMETA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360103* -- Metals & Alloys-- Mechanical Properties
360105 -- Metals & Alloys-- Corrosion & Erosion
CHEMICAL REACTIONS
CRYSTAL STRUCTURE
ELEMENTS
EMBRITTLEMENT
FRACTURE PROPERTIES
HYDRIDATION
LOW TEMPERATURE
MECHANICAL PROPERTIES
METALS
MICROSTRUCTURE
NIOBIUM
REFRACTORY METALS
TEMPERATURE DEPENDENCE
TRANSITION ELEMENTS