TOPOTACTICAL REARRANGEMENT IN ALC4B24 AND PREPARATION OF A NEW BORON CARBIDE TYPE STRUCTURE.

Abstract

Single crystals of AlC4B24 undergo an irreversible rearrangement at high temperatures to a boron carbide type structure. During the reaction the form of the original single crystal is not altered, which enables tracing of the crystallographic axes during the transition. The rearrangement can be expressed in terms of a change in packing from hexagonal closest to cubic losest packing of icosahedral boron groups. The boron carbide phase contains a variable amount of aluminum over the composition range of B12C2Al25 - B12C2Al.75. This range is interpreted to be part of a homogeneity range between a boron carbide B12C2 and a ternary phase B12C2Al. (Author)

Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1964
Accession Number
AD0608443

Entities

People

  • J. Economy
  • R. F. Giese Jr.
  • V. I. Matkovich

Tags

DTIC Thesaurus Topics

  • Aluminum
  • Boron Carbides
  • Carbides
  • Crystals
  • High Temperature
  • Homogeneity
  • Metals
  • Single Crystals
  • Transition Metals
  • Transitions

Fields of Study

  • Chemistry

Readers

  • Materials Science and Engineering.
  • Quantum Chemistry