Accession Number : AD0442590

Title :   DEVELOPMENT OF FRONTAL SECTION FOR SUPER-ORBITAL, LIFTING, RE-ENTRY VEHICLE. VOLUME II: MATERIALS AND COMPOSITE STRUCTURE DEVELOPMENT.

Descriptive Note : Final rept., July 61-May 64,

Corporate Author : SOLAR TURBINES INTERNATIONAL SAN DIEGO CA

Personal Author(s) : Licciardello, M. R. ; Ohnysty, B. ; Stetson, A. R.

Report Date : 29 MAY 1964

Pagination or Media Count : 248

Abstract : Development of a tungsten/thoria composite structure suitable for use on super-orbital, lifting, re-entry vehicle nose caps is presented. Tungsten was chosen as the structural material, based on extensive testing of oxidation behavior, compatibility, and mechanical properties. Thorium oxide was selected as the thermal protection system, based on high melting point, good compatibility, and high emittance at high temperature. In addition, thoria was found to sublime rather than melt at high temperature with pressures less than 0.75 atmosphere. This factor was used to allow exposure to high heat pulses of short duration. Extensive materials data are presented on measurement of emittance, expansion coefficient, thermal conductivity, oxidation resistance, and compatibility of thoria, hafnia, and zirconia. Some data on selected carbides are also included. Thoria, chemically bonded with thorium nitrate, was selected as the coating. The coating exhibited shrinkage of less than 1 percent after exposure to 5200 F for 5 minutes.(Author)

Descriptors :   *LIFTING REENTRY VEHICLES), (*NOSE CONES, (*NOSE CONES, REFRACTORY METALS), COMPOSITE MATERIALS, CERAMIC COATINGS, TANTALUM, TUNGSTEN, TANTALUM ALLOYS, TUNGSTEN ALLOYS, HAFNIUM ALLOYS, OXIDATION, STRESSES, RUPTURE, COMPATIBILITY, THERMAL CONDUCTIVITY, THERMAL EXPANSION, DIOXIDES, THORIUM COMPOUNDS, HAFNIUM COMPOUNDS, PLASMA JETS, PERFORMANCE(ENGINEERING), REFRACTORY COATINGS, ZIRCONIUM OXIDES, MAGNESIUM OXIDES.

Distribution Statement : APPROVED FOR PUBLIC RELEASE