THE EFFECT OF SOLUTE-IMPERFECTION INTERACTIONS UPON PLASTICITY AND FRACTURE.

Abstract

This reort is concerned with an investigation of the effect of solute-imperfection interactions upon plasticity and fracture. Insofar as the yielding of materials that deform in a heterogeneous manner are concerned, we have demonstrated that the addition of a hard noncoherent particle such as aluminum oxide to alpha-iron results in a modification of the yielding, flow, and strain aging of the alpha-iron. The hard particles appear to act as dislocation sources and to effect the velocity of dislocations in the alpha-iron matrix. From these results, it is suggested that the aluminum additions made in the production of ''killed'' steel has two roles: (1) the well known chemical effect of decreasing the nitrogen content by the formation of a nitride and (2) from our work a physical effect probably due to the trapping of interstitial elements at dislocations associated with the inclusions formed in the deoxidation and denitriding practice. An experimental investigation of the influence of departure from stoichiometry upon plasticity in NiAl revealed that the compressive yield stresses were in general higher for the substitutional defects (high Ni composition) than for the vacancies (low Ni compositions). (Author)

Document Details

Document Type
Technical Report
Publication Date
Oct 31, 1963
Accession Number
AD0428334

Entities

People

  • J. O. Brittain

Organizations

  • Northwestern University

Tags

DTIC Thesaurus Topics

  • Aluminum
  • Aluminum Oxides
  • Dislocations
  • Elements
  • Films
  • Inclusions
  • Materials
  • Nitrogen
  • Oxides
  • Particles
  • Plastic Properties
  • Production
  • Stoichiometry

Fields of Study

  • Materials science

Readers

  • Powder metallurgy of Titanium alloys.