METHOD AND APPARATUS FOR DETERMINING THERMAL RESISTANCE AND STRUCTURAL INTEGRITY OF COATINGS ON CONDUCTING MATERIALS BY MONITORING ELECTRICAL CONDUCTANCE OF THE UNDERLYING MATERIAL UPON LOCALIZED HEATING OF THE OVERLYING COATING

摘要

A system for nondestructive analysis of barrier coatings on electrically conductive materials includes imposition of a controlled known heat load (16) to a localized area of the coating (12) and measuring electrical conductivity of the underlying material (10) at or near the localized area of the coating (12). The electrical conductivity of the material (10) is affected by changes in temperature related to thermal conduction into the material (10) through the coating (12). Thermal resistance of the coating (12) and defects between the coating (12) and the material (10) can therefore be detected.