THE EFFECT OF STRESS ON SOLID STATE PHASE TRANSFORMATIONS.

Abstract

The objective of this research was to gain a better understanding of the factors which control the occurrence and characteristics of martensitic transformations. A very simple transformation was chosen -- face-centered cubic to hexagonal close packed -- because it offered the best opportunity to understand the mechanism. The shears which take place may be attributed to the passage of Shockley partial dislocations over every other close-packed plane. There is a well-developed body of knowledge about the movement of dislocations under stress, to effect slip and twinning. It was hoped that the effect of stress on the martensitic transformation could be interpreted in terms of what is known about slip and twinning. Transformation in cobalt, and cobalt-nickel single and polycrystals was carried out under a series of applied stresses. Transformations in carium and lanthanum polycrystals were studied by x-ray diffraction, dilatometry and metallographic techniques. (Author)

Document Details

Document Type
Technical Report
Publication Date
Sep 02, 1968
Accession Number
AD0673301

Entities

People

  • Carl J. Altstetter

Organizations

  • University of Illinois Urbana–Champaign

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Crystal Structure
  • Diffraction
  • Dislocations
  • Lanthanum
  • Phase Transformations
  • Polycrystals
  • Wave Phenomena
  • X Rays
  • X-Ray Diffraction

Readers

  • Materials Science and Engineering.