INVESTIGATION OF INTERMETALLIC COMPOUNDS FOR VERY HIGH TEMPERATURE APPLICATIONS. Progress Report No. 5 for April 16, 1960 to July 15, 1960. Technical Report No. 183

Progress on the properties of intermetallic beryllides and silicides under investigation is reported. Evaluation of the oxidation resistance of Hf/ sub 2/Be/sub 21/ and WSi/sub 2/ is discussed. Introductory work on the quantitative determination of the rate of oxidation of ZrBe/sub 13/ is reported. The oxidation products of this compound are identified as ZrBe/sub 17/ and BeO and the over-all rate of oxidation follows the cubic rate law. Thermal expansion data for WSi/sub 2/ and enthalpy data for Ta/sub 2/Be/sub 17/ are given. With these data the experimental measurement of thermal expansion and enthalpy are completed for all the compounds under investigation. Additional transverse- rupture data are reported for WSi/sub 2/ and Hf/sub 2/Be/sub 17/. (auth)