Accession Number : AD0465268


Title :   A METALLURGICAL EVALUATION OF VARIOUS COMMERCIAL INFILTRATED TUNGSTEN MATERIALS IN AIR AND NITROGEN PLASMAS.


Descriptive Note : Technical documentary rept.,


Corporate Author : AEROSPACE CORP EL SEGUNDO CA


Personal Author(s) : White, J E ; Leeds, D H


Report Date : 01 May 1965


Pagination or Media Count : 35


Abstract : Increasingly severe oxidation and erosion conditions for unprotected reentry vehicle surfaces, and for rocket engine nozzle applications, have shown the need for study of infiltrantcontaining tungsten structures under oxidizing conditions. Tests on several infiltrated alloys were conducted in both subsonic air and nitrogen plasma arcs, delivering cold wall heat fluxes of 700 Btu/sq ft-sec, 1200 Btu/sq ft-sec, and 2400 Btu/sq ft-sec. Thermal arrest, recession rate, and mass loss were examined as a function of atmosphere, heat flux, and composition for each material. The material changes were examined metallographically and by electron micro-probe techniques to compare commercially available brass-infiltrated tungsten; with silver, with 80 Sn-20 Al and with 90 Cu-10 Si-infiltrated tungsten materials. Infiltrant depleted zone formation, oxidation protection, blockage of matrix transpirant paths, and infiltrant-matrix reactions were of specific interest for comparison with solid tungsten. (Author)


Descriptors :   *TUNGSTEN , EVAPOTRANSPIRATION , ATMOSPHERE ENTRY , SILVER , TIN ALLOYS , ALUMINUM ALLOYS , COPPER ALLOYS , SILICON , PLASMAS(PHYSICS) , HIGH TEMPERATURE , MICROSTRUCTURE , OXIDES , AIR , NITROGEN , GRAIN STRUCTURES(METALLURGY) , BRASS , IMPREGNATION , POWDER METALS


Distribution Statement : APPROVED FOR PUBLIC RELEASE