Determination of Thermal Control Coating Emissivity and Absorptivity Indicatrixes

The methods and facilities for determination of emissivity and absorptivity indicatrixes of materials and coatings are presented.

The method for determination of emissivity indicatrix is based on diaphragming and measuring the axisymmetric radiant fluxes of a test sample. Two variants of the method realization are considered. The method and facility permit the investigation of the coatings on metals and insulation over the temperature range up to 1100 K to be carried out.

The absorptivity indicatrixes are determined by means of a calorimetric method based on irradiating a test sample by collimating radiant flux. The method is realized for determination of solar absorptivity indicatrixes of coatings on any opaque materials in simulated space environment.

The emissivity and absorptivity indicatrixes of several coatings are presented.