An Apparatus for Measuring Thermal Conductivities to 2 degrees K. Measurements in Single Crystal Halides as a Function of Dislocation Density.

Abstract

A thermal conductivity apparatus was constructed and used to measure the thermal conductivity of a single crystal of sodium chloride as a function of dislocation density, N. The temperature range of the measurements was 2.5 to 40K. The temperatures were measured with gold (.02 atomic % iron) vs. chromel thermocouples, and germanium resistance thermometers. A well defined maximum was observed in the thermal conductivity at around 10K, the value of which was three times greater in an annealed crystal (minimum number of dislocations) than it was in the unannealed crystal. A relationship of K = 0.049(T to the 2.7 power)/(N to the 0.8 power) was observed between T equal to 7 and 2K for the thermal conductivity vs. temperature. (Author)

Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1972
Accession Number
AD0759552

Entities

People

  • George L. Haury

Organizations

  • Air Force Research Laboratory

Tags

DTIC Thesaurus Topics

  • Conductivity
  • Crystals
  • Dislocations
  • Measurement
  • Resistance Thermometers
  • Single Crystals
  • Sodium Compounds
  • Thermal Conductivity
  • Thermometers

Fields of Study

  • Materials science

Readers

  • Materials Science and Engineering.
  • Thermal Physics or Thermal Science.