This document specifies a test method for determination of the thermal conductivity of ceramics coatings on ceramic or metal substrate at the direction perpendicular to the surface by using relative method. Procedures for calculation, data collection, and reporting are given.

This document is applicable primarily to the ceramic coatings on ceramic or metal substrates. The applicable coatings are thin ceramic coatings used as a thermal barrier coating, environmental barrier coating and wear-resistant coating. This document is applicable for coating thickness to substrate thickness ratios greater than 1/100 and less than 1/500. While this ratio range it is too low for direct measurement methods, the calculation specified in this document is effective for estimating the thermal conductivity of the coating in this range, including thermal resistance.