Open AccessTHE NEEDLE-LIKE STRESS ZONES AND DISLOCATIONS DUE TO CONSTITUTIONAL SUPERCOOLING IN CZOCHRALSKI METHOD-GROWN YAG SINGLE CRYSTALS
Author(s) -
Ge Chuan-Zhen,
Xu Xiu-Ying,
Feng Ding
Publication year - 1981
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.30.218
Subject(s) - materials science , supercooling , dislocation , birefringence , stress (linguistics) , czochralski method , condensed matter physics , elasticity (physics) , optics , doping , composite material , thermodynamics , optoelectronics , physics , linguistics , philosophy
In this paper, we studied the relationship between the morphological development of the solid-liquid interface and the needle-like stress zones in Czochralskimethod-grown YAG single crystals doped with Nd. The experimental results established that the needle-like stress zones were originated from the solute (Nd) -rich zones due to constitutional supercooling. By studying the needle-like stress zones with photo-elasticity method, the stress in these zones was found to be axially symmetrical comperssive. We have also studied dislocation arrays along the boundaries of solute (Nd)-rich zones by means of etching method and birefringence observation, and measured the dis location density. The measured density agrees roughly with the value estimated according to the theory of misfit dislocations.