The Mechanism of Hydrogen Embrittlement in Nickel.

Abstract

Grain boundary cracking associated with the decomposition of nickel hydride in cathodically charged nickel was studied in the high voltage electron microscope. The occurrence of grain boundary cracking comes about from the presence of hydrogen at the boundaries and is not solely the result of the local boundary tensile stress due to the 5% difference in lattice parameter between the nickel and the hydride phases. In thin foil specimens grain boundary cracking occurs in the period of a few minutes after the end of cathodic charging, and does not continue in electron transparent regions during observation in the high voltage microscope. The susceptibility of grain boundaries to hydrogen-induced cracking is strongly dependent upon the structure of the boundary. Special boundaries, such as that of a twin, are particularly resistant to cracking.

Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1975
Accession Number
ADA021728

Entities

People

  • Peter R. Swann
  • Stephen L. Sass

Organizations

  • Imperial College London

Tags

DTIC Thesaurus Topics

  • Boundaries
  • Decomposition
  • Electron Microscopes
  • Electrons
  • Embrittlement
  • Grain Boundaries
  • High Voltage
  • Hydrogen
  • Hydrogen Embrittlement
  • Microscopes
  • Observation
  • Stresses
  • Tensile Stress
  • Voltage

Fields of Study

  • Materials science

Readers

  • Electrochemical Engineering/ Fuel Cell Technologies
  • Fluid Dynamics.
  • Materials Science (Mechanical Engineering).

Technology Areas

  • Microelectronics