LOW-TEMPERATURE SPONTANEOUS TRANSFORMATIONS IN FINE-GRAINED ALKALI METALS

Abstract

IN THE COURSE OF DIFFRACTION EXPERIMENTS ON LITHIUM, SODIUM, AND POTASSIUM COOLED TO 1.4 K, observations were made on the quantity of transformed phase and the temperture region in which this transformation occurs. Two samples of lithium were used. The first was of very pure metal of rather large grain size; the second was less pure, but fine-grained. Both samples showed spontaneous transformation to hcp (hexagonal close-packed) and fcc. The behavior of a fine-grained sodium sample in the same temperature range was quite different. Upon the first cooling to 1.4 K, no low-temperature phase appeared. After being warmed to 77 K and again cooled, the hcp phase appeared in considerable quantity. No spontaneous transformation was detected in a fine-grained sample of potassium to 1.4 K. (Author)

Document Details

Document Type
Technical Report
Publication Date
Feb 01, 1961
Accession Number
AD0258132

Entities

People

  • C.h. Shaw
  • K.d. Alexopoulos

Organizations

  • Ohio State University

Tags

DTIC Thesaurus Topics

  • Alkali Metals
  • Diffraction
  • Elements
  • Grain Size
  • Low Temperature
  • Metals
  • Observation
  • Potassium

Readers

  • Materials Science and Engineering.