Accession Number:

AD0652828

Title:

THERMODYNAMIC STUDY OF SYNTHESIS OF NEW COMPOUND PHASES UNDER HIGH PRESSURE

Descriptive Note:

Corporate Author:

MANLABS INC CAMBRIDGE MA

Report Date:

1967-02-01

Pagination or Media Count:

53.0

Abstract:

A phenomological analysis and correlation of available volumetric and entropy data was performed for the III-V compounds. The results of these procedures were used to predict the volumetric properties of the known high pressure forms of BN and the unknown forms of BSb. In addition, values for compound entropy and the entropy of formation were predicted for the above compounds, BN and BSb, and for several known III-V compounds for which such data are presently lacking. The value for the P-T coefficient, was also calculated from the predicted quantities for the BN transformations and for the synthesis of BSb from the elements. An experimental program was carried out to attempt to synthesize a new compound BSb. The results obtained suggest that the B-Sb system at 50 kilobars is characterized by a miscibility gap in the liquid phase. High pressure experiments were also carried out for AlN the results obtained show that solid aluminum nitride and solid boron nitride react by a diffusion process which produces marked changes in the microhardness and morphology of the boron nitride.

Subject Categories:

  • Inorganic Chemistry
  • Ceramics, Refractories and Glass

Distribution Statement:

APPROVED FOR PUBLIC RELEASE