Accession Number:

AD0855693

Title:

Defects in Body Centred Cubic Metals and Alloys.

Descriptive Note:

Final technical rept. 1 Oct 66-30 Sep 68,

Corporate Author:

OXFORD UNIV (UNITED KINGDOM) DEPT OF METALLURGY

Report Date:

1969-05-01

Pagination or Media Count:

77.0

Abstract:

The dislocation arrangements in deformed single crystals of high purity niobium, and some of its alloys with molybdenum and rhenium, have been studied using transmission electron microscopy. In niobium the arrangements corresponding to various points on the stress-strain curve have been ascertained in detail. A general theory is developed to account for the mobility of a dislocation which is sessile in its low-energy form. A specific core model is used to derive an expression for the mobility of screw dislocations in body centred cubic metals, and the application of the theory to the temperature and orientation dependence of the yield stress and slip geometry, and to the stress dependence of the activation energy and volume is discussed. Author

Subject Categories:

  • Metallurgy and Metallography
  • Crystallography
  • Solid State Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE