Accession Number : AD0379195

Title :   DENSIFICATION OF LMH-2.

Descriptive Note : Quarterly rept. no. 1, 2 May-29 Jul 66,

Corporate Author : ETHYL CORP BATON ROUGE LA

Personal Author(s) : Brendel,G. J. ; Marlett,E. M.

Report Date : SEP 1966

Pagination or Media Count : 24

Abstract : Ultra-high pressure hydrostatic equipment was obtained for use in BeH2 crystallization studies. During its installation the crystallization of high-purity Li-doped BeH2 (96 wt % BeH2, 1.3 wt % Li) was investigated using an improved design piston-mold apparatus. The high purity feed material tended to give a product with relatively high concentrations of crystalline Phase 338-208 and densities in the range 0.75-0.77 g/cc. As the pressure and temperature was increased, Phase 378-295 formed preferentially, as expected. Its density approached a value of 0.80-0.82 g/cc. Rate of temperature quench under pressure had no effect on extent of crystallization or polymorph distribution. On the other hand, a rapid pressure quench at elevated temperature is detrimental to the crystallization process. It was found that amorphous BeH2 can be prepared in a fused, glassy state by pre-compaction, then heating without pressure to 170-200C. Investigation of impurities in BeH2 showed that the presence of butoxide groups in the pyrolysis feed, di-t-butylberyllium etherate, enhanced the thermal stability of the t-butyl groups. This information aided the production of the highest purity Li-doped BeH2 obtained to date. Attempts to improve purity even further by hydrogenolysis of residual alkyl groups proved unsuccessful. (Author)

Descriptors :   (*ROCKET PROPELLANTS, SCIENTIFIC RESEARCH), PRESSURE, TEMPERATURE (U) *HYDRIDES, *SOLID ROCKET PROPELLANTS, *BERYLLIUM COMPOUNDS, LITHIUM COMPOUNDS, CRYSTALLIZATION, PURIFICATION, DOPING, LITHIUM, THERMAL STABILITY

Subject Categories : Rocket Propellants
      Solid Rocket Propellants

Distribution Statement : APPROVED FOR PUBLIC RELEASE