US 2003008065 A1 abstract a reference standard and method for inspecting dual layered coatings the reference standard has a first layer adherent to a substrate the first layer has a predetermined thickness that increases in one direction adherent to the first layer is a second layer the second layer has a predetermined thickness that increases in a direction orthogonal with the first layer the orientation of the first and second layers of the reference standard provides a spectrum of the possible variations of the dual layered coating application_number US 17318102 A description the present invention is generally applicable to inspection of components that operate within the environment of a gas turbine engine characteristics of the environment include relatively high temperatures and are therefore subjected to severe thermal stresses and thermal cycling notable examples of such components include high and low pressure turbine nozzles and blades shrouds combustor liners and augmentor hardware of gas turbine engines one such example is the high pressure turbine blade 10 shown in fig1 0017 fig2 is a cross sectional view of a portion of the turbine blade of fig1 represented in fig2 is a thermal barrier coating system 20 as shown the thermal barrier coating system 20 is a dual layered coating the dual layered coating is comprised of a ceramic layer 26 adherent to the bond layer 24 the bond layer 24 is adherent to the.