Logo RUB
  • Institute
    • ICAMS
      • Mission
      • Structure
      • Members
      • Fellows
    • Departments & Research Groups
      • Atomistic Modelling and Simulation
      • Scale-Bridging Thermodynamic and Kinetic Simulation
      • Micromechanical and Macroscopic Modelling
      • Artificial Intelligence for Integrated Material Science
      • Computational Design of Functional Interfaces
      • Scale-Bridging Simulation of Functional Composites
      • Materials Informatics and Data Science
      • High-Performance Computing in Materials Science
    • Central Services
      • Coordination Office
      • IT
  • Research
    • Overview
    • Publications
    • Software and Data
    • Collaborative research
    • Research networks
    • Young enterprises
  • Teaching
    • Overview
    • Materialwissenschaft B.Sc.
    • Materials Science and Simulation M.Sc.
    • ICAMS Graduate School
    • Student Projects
  • News & Events
    • Overview
    • News
    • Seminars and Workshops
    • Conferences
  • Services
    • Overview
    • Contact
    • Open positions
    • Travel information
 
ICAMS
ICAMS
MENÜ
  • RUB-STARTSEITE
  • Institute
    • ICAMS
    • Departments & Research Groups
    • Central Services
  • Research
    • Overview
    • Publications
    • Software and Data
    • Collaborative research
    • Research networks
    • Young enterprises
  • Teaching
    • Overview
    • Materialwissenschaft B.Sc.
    • Materials Science and Simulation M.Sc.
    • ICAMS Graduate School
    • Student Projects
  • News & Events
    • Overview
    • News
    • Seminars and Workshops
    • Conferences
  • Services
    • Overview
    • Contact
    • Open positions
    • Travel information
Home » Research » Publications

Just another WordPress site - Ruhr-Universität Bochum

Hydrogen-enhanced local plasticity at dilute bulk H concentrations: The role of H-H interactions and the formation of local hydrides

J. von Pezold, L. Lymperakis, J. Neugebauer

Acta Materialia, 59, 2969-2980, (2011)

DOI: 10.1016/j.actamat.2011.01.037

Download: BibTEX

The effect of H on the stress-mediated dislocation-dislocation interaction in face-centered cubic metals is studied by a hierarchical approach combining ab initio electronic structure calculations, semi-empirical embedded atom method potentials and a lattice-gas Hamiltonian, using the NiH system as a model system. The H distribution around edge dislocations is found to depend critically on H-H interactions within the metal matrix. In the absence of these interactions a dilute H distribution is obtained at realistic bulk H concentrations. In contrast, our calculations show that even a weakly attractive interaction between interstitial H atoms in the host matrix dramatically increases the local H concentration in the tensile strain field of the dislocation, resulting in the formation of a local hydride phase along the dislocation line. While in the absence of any H-H interactions huge bulk H concentrations of the order of 10 at.% are required to induce the stress shielding effect underlying the hydrogen-enhanced local plasticity (HELP) mechanism, the presence of even weak H-H interactions dramatically reduces the onset H concentration of HELP. As a consequence bulk H concentrations as low as 1.6 x 10(-2) at.% (160 ppm) may result in embrittlement. The formation of a local hydride induces a strong, short-range shielding effect along the slip plane of the dislocation, while normal to the glide plane the shear stress is predominantly increased. The stress shielding effect is correlated with a reduced dislocation separation at dislocation pile-up tips, which may result in the nucleation of microcracks and hence the onset of embrittlement.

back
{"type":"article", "name":"j.vonpezold20118", "author":"J. von Pezold and L. Lymperakis and J. Neugebauer", "title":"Hydrogenenhanced local plasticity at dilute bulk H concentrations: The role of HH interactions and the formation of local hydrides", "journal":"Acta Materialia", "volume":"59", "OPTnumber":"8", "OPTmonth":"8", "year":"2011", "OPTpages":"2969-2980", "OPTnote":"", "OPTkey":"Hydrogen embrittlement; Modeling; Monte Carlo technique; Ab initio electron theory", "DOI":"10.1016/j.actamat.2011.01.037"}
Logo RUB
  • Open positions
  • Travel information
  • Imprint
  • Privacy Policy
  • Sitemap
Ruhr-Universität Bochum
Universitätsstraße 150
44801 Bochum

  • Open positions
  • Travel information
  • Imprint
  • Privacy Policy
  • Sitemap
Seitenanfang Kontrast N