Hydrostatic Pressure Induced Ductility Transitions in Pure Bismuth and Tin-Bismuth Alloys.

Abstract

The mechanical behavior of pure (99.999%) bismuth and tin-bismuth alloys of various compositions has been observed over a range of superimposed hydrostatic pressures. Results indicate that maxima in ductility (as measured by percent reduction in area at the fracture surface) in specimens tested at atmospheric pressure occur at compositions bordering pure tin and the eutectic composition. At sufficiently high pressures all compositions failed by rupture, i.e. necking to virtually 100% RA. For pure bismuth, pressure was observed to retard failure due to the formation of cracks at twin-grain boundary intersections; this result was consistent with the hypothesis that the effect of pressure is to shift the mode of crack propagation by decreasing the normal tensile component of stress acting on a crack. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1973
Accession Number
AD0764241

Entities

People

  • J. Pepe
  • P. V. Dembowski
  • T. E. Davidson

Tags

DTIC Thesaurus Topics

  • Alloys
  • Barometric Pressure
  • Bismuth
  • Bismuth Alloys
  • Boundaries
  • Crack Propagation
  • Cracks
  • Ductility
  • Grain Boundaries
  • High Pressure
  • Hydrostatic Pressure
  • Transitions

Readers

  • Materials Science (Mechanical Engineering).
  • Materials Science and Engineering.