Accession Number : AD0284945

Title :   INVESTIGATION OF INTERMETALLIC COMPOUNDS FOR VERY HIGH TEMPERATURE APPLICATIONS

Corporate Author : BRUSH BERYLLIUM CO CLEVELAND OHIO

Personal Author(s) : BOOKER,JONATHAN ; PAINE,ROBERT M. ; STONEHOUSE,A. JAMES

Report Date : JUL 1962

Pagination or Media Count : 1

Abstract : Three areas were studied in a continuing investigation of intermetallic beryllides and silicides for very high temperature applications. The measured properties of Ta2Be17 were unaffected by minor variations in stoichiometry between 800 and 3000 F, whereas best results for WSi2 were obtained with a material slightly deficient in W. WSi2 exhibited poorest oxidation resistance at 2200 F. Results are reported for oxidation-rate studies on TaBe12, Ta2Be17, ZrBe13, and Zr2Be17 in the temperature range from 2300 to 2750 F. The vapor pressures for these same compounds were measured between 2300 and 2650 F, using the Knudsen cell technique. For TaBe12 the activation energy for oxidation is lower than the vaporization energy in this temperature range. The oxidation products of Zr2Be17 were ZrBe5 and BeO. Ternary systems of Be and Si with Mo, Nb, Ta, W, or Zr were studied. The most promising was a mixed-phase preparation with the stoichiometry of MoBeSi, which exhibited less than 2 mils penetration when oxidized in air at 3000 F for 10 hr. (Author)

Descriptors :   *BERYLLIUM COMPOUNDS, *INTERMETALLIC COMPOUNDS, *REFRACTORY MATERIALS, *TANTALUM COMPOUNDS, *TUNGSTEN COMPOUNDS, *ZIRCONIUM COMPOUNDS, ANTIOXIDANTS, FRACTURE (MECHANICS), HIGH TEMPERATURE, IMPACT SHOCK, OXIDATION, PHYSICAL PROPERTIES, REACTION KINETICS, SILICIDES, THEORY, THERMAL CONDUCTIVITY, THERMAL STRESSES, VAPOR PRESSURE

Distribution Statement : APPROVED FOR PUBLIC RELEASE