SELF-DIFFUSION IN DELTA IRON

Abstract

Self-diffusion of Fe was measured in delta Fe between 1404 and 1518 C. Although the delta Fe results are adequately described by the equation D equals 0.019 exp (-42400/RT) sq cm per sec, in order to join these coefficients in a reasonable way with the self-diffusion coefficients of alpha Fe, it is necessary to introduce a curved line in the plot of logarithm of diffusivity versus reciprocal of absolute temperature. Although this curved line diminishes the magnitude of the Curie point anomalies observed for self-diffusion in alpha Fe and probably for diffusion in Fe-V alloys, it does not appear that the excess vacancy formation energy arising from spin ordering is enough to account for the whole Curie point effect. Possible ways to obtain information about changes in the activation energy for vacancy motion are discussed. (Author)

Document Details

Document Type
Technical Report
Publication Date
Apr 09, 1961
Accession Number
AD0259447

Entities

People

  • C. Ernest Birchenall
  • Lars I. Staffansson

Organizations

  • University of Delaware

Tags

DTIC Thesaurus Topics

  • Coefficients
  • Curie Temperature
  • Diffusion
  • Diffusion Coefficient
  • Diffusivity
  • Energy
  • Equations
  • Heat Of Activation
  • Mathematics
  • Physical Properties

Readers

  • Analytical Mechanics
  • Materials Science and Engineering.