THERMOPHYSICAL PROPERTIES OF ALLOYS IN THE SYSTEMS BORON-NITROGEN, BORON-CARBON, SILICON-NITROGEN, AND BORON-SILICON-CARBON,
Abstract
The paper deals with an investigation of the properties of a number of high-temperature semiconducting alloys manufactured by powder metal methods. It is shown that the compound BN in the boron-nitrogen system possesses an extensive region of homogeneity; the rearrangement of the boron lattice during nitrogenization leads to the formation of alloys in the nitride homogeneity region with predominance of electronic conductivity. With an increase in the nitrogen content in the nitride the electrical resistance of the latter sharply rises up to 35-38 percent of nitrogen, after which the rise in resistance is decelerated, which is accounted for by the participation in the conductivity of electrons effecting the bonds between the plane layers of atoms in the nitride structure. It is established that Si3N4 is a semiconductor. The nature of the effect of additions of carbon and titanium on silicon nitride conductivity is shown. The author shows the existence of two carbides - B4C and B12C - in the boron-carbon system. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 14, 1969
- Accession Number
- AD0696303
Entities
People
- G. V. Samsonov
Organizations
- National Air and Space Intelligence Center