Accession Number : AD0266801

Title :   THERMOGRAPHIC PROFILES OF MATERIAL DISCONTINUITIES

Corporate Author : ARMY TANK-AUTOMOTIVE CENTER WARREN MICH

Personal Author(s) : WILBURN,DAVID K.

Report Date : 01 MAR 1961

Pagination or Media Count : 1

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)

Descriptors :   *NONDESTRUCTIVE TESTING, *RADIOMETERS, DETECTION, INFRARED PULSES, INFRARED SCANNING, INSTRUMENTATION, MATERIALS, MEASUREMENT, SENSITIVITY, SOLIDS, TEMPERATURE, THERMAL CONDUCTIVITY, THERMAL RADIATION, THERMIONIC EMISSION

Distribution Statement : APPROVED FOR PUBLIC RELEASE