Procedures for the Precise Determination of Thermal Radiation Properties.

The broad objective of this program is to develop equipment and procedures for measuring the important thermal radiation properties of materials, particularly those used in aircraft, missiles, and space vehicles, at temperatures up to the melting points of the most refractory materials. During the period covered by this report the specific objectives were to complete development of the laser-source integrating sphere reflectometer, and to prepare emittance standards for use at temperatures above 1400 K (1200F). The laser-source integrating sphere reflectometer consisted of (1) a 35 cm (20 The laser-source integrating sphere reflectometer consisted of (1) a helium-neon laser as a source, capable of operation at 0.6328, 1.15, and 3.39 micrometers; (2) a 35 cm (14 inc.) diameter sphere coated with barium sulphate or sodium chloride; (3) a lead sulfide detector; and (4) a radio-frequency generator for heating the sample by induction. (Author)