Accession Number : AD0801274

Title :   THE ROLE OF EMITTANCE IN REFRACTORY METAL COATING PERFORMANCE: PART I - REVIEW AND ANALYSIS.

Descriptive Note : Summary technical rept. 1 Jul 65-31 Jan 66 on Phase 1,

Corporate Author : NORTH AMERICAN AVIATION INC LOS ANGELES CA

Personal Author(s) : Bartsch, K. O. ; Huebner, A.

Report Date : JAN 1966

Pagination or Media Count : 153

Abstract : The role of emittance was reviewed for the purpose of orienting the planning of a comprehensive program to provide accurate and proper emittance data for thermal calculations needed in the design of advanced aerospace vehicles and engines. The following was found: Coated refractory metals are used and are planned for future use on reentry and hypersonic cruise vehicles which are cooled almost solely by the radiation of heat to space. Space engine nozzles and extensions fabricated of coated refractory metals may be cooled to advantage by radiation. Emittance values have a profound effect on the rate of heat rejection, and thereby, on the metal-coating system temperature which, in turn, controls coating life and metal strength. The emittance of a coated refractory metal is a function of its environment which includes temperature, time, partial pressures of the atmospheric constituents, and the free-stream velocity of the atmosphere under extreme temperature conditions.

Descriptors :   *EMISSIVITY), (*REFRACTORY COATINGS, (*REFRACTORY METALS, REFRACTORY COATINGS), AEROSPACE CRAFT, ROCKET ENGINES, COOLING, SILICIDES, NIOBIUM ALLOYS, MOLYBDENUM ALLOYS, TIN, ALUMINUM COMPOUNDS, TANTALUM ALLOYS, THERMAL RADIATION, HYPERSONIC FLOW.

Subject Categories : Coatings, Colorants and Finishes

Distribution Statement : APPROVED FOR PUBLIC RELEASE