THE GROWTH OF SINGLE CRYSTALS OF DOPED AND UNDOPED YTTRIA AND YTTRIUM ALUMINATE IN A HOLLOW CATHODE ZONE REFINER.

Abstract

This report describes the results of Y2O3 and YAlO3 crystal growth efforts. A hollow cathode float-zone process was employed to achieve single crystal growth. During this period, single crystals of Y2O3 were grown but exhibited thermal cracking. Float-zone studies of 1 Y2O3 : 1 Al2O3 revealed that YAlO3 can be crystallized from the stoichiometric melt. It appears that YAlO3 crystallizes incongruently but that the molten zone compositional changes which occur during scanning may permit the growth of single crystal YAlO3. The instrumental changes made during this quarter include a new scanning system to permit improved rotation of crystal and feed rod during growth, and a dark space shielded hollow cathode gun. Several afterheater arrangements have been incorporated into the system to limit the thermal gradients on the growing crystal.

Document Details

Document Type
Technical Report
Publication Date
Jul 15, 1966
Accession Number
AD0487286

Tags

DTIC Thesaurus Topics

  • Aluminates
  • Crystal Growth
  • Crystallization
  • Crystals
  • Rotation
  • Scanning
  • Single Crystals

Fields of Study

  • Materials science

Readers

  • Electronics Engineering
  • Materials Science and Engineering.

Technology Areas

  • Space
  • Space - Hall-Effect Thruster