Analysis of paint thickness based on flash pulse thermography

Abstract

Coating thickness (thermal barrier coatings, anticorrosion paints, etc.) can influence its properties and therefore the thickness is often measured in industrial application. This contribution describes fast areal thickness estimation based on flash pulse thermography. Specimens sprayed by a black paint on AISI 304 substrates were used for a demonstration of the thickness estimation. Two different types of post-processing and thickness estimation were used: functional calibration with FFT (phase) and analytical model. Both procedures were compared and both provided satisfactory results with maximum error of thickness estimation less than 10 %. Advantages and disadvantages of proposed techniques are discussed.