THERMOGRAPHIC PROFILES OF MATERIAL DISCONTINUITIES

Abstract

An infrared line scan radiometer was utilized to obtain thermal patterns representative of interior discontinuities in solids of low heat conductivity. Temperature differences as low as 0.6 C could be detected with a theoretical resolution of 0.031 inches. Non-metals with thermal conductivity k, below 0.01 cal/sqcm/sec/degree C/sec can be examined by this method. Metals and non-metals with k values above 0.1 cal/sqcm/sec/degree C/sec dissipate surface thermal gradients too rapidly to produce a sufficient temperature difference for detection. The radiometer system is evaluated with respect to parameters of frame time, bandwidth and sample distance. Typical thermograms are presented for a variety of insulating and other low k value materials. (Author)

Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1961
Accession Number
AD0266801

Entities

People

  • David K. Wilburn

Organizations

  • United States Army Tank Automotive Research, Development and Engineering Center

Tags

DTIC Thesaurus Topics

  • Bandwidth
  • Conductivity
  • Detection
  • Discontinuities
  • Isotherms
  • Materials
  • Physical Properties
  • Radiometers
  • Temperature Gradients
  • Thermal Conductivity
  • Thermophysical Properties

Fields of Study

  • Physics

Readers

  • Radar Systems Engineering.
  • Thermal Physics or Thermal Science.

Technology Areas

  • Microelectronics