Abstract
A laser-heated floating zone technique is employed to grow a filamentary c-axis sapphire. Crystal growth is directly recorded during the process by photography, and crystals grown under various conditions are examined by means of a transmission optical microscope to obtain the relationships between microvoid formation and growth conditions. Observations of filaments indicated that the microvoid results from shrinkage due to dendritic growth. Microvoids are eliminated by choosing a growth rate less than 4.7 cm h−1 or by focusing the laser beam. By using this method, a void-free filament of 1.4 mm diameter is obtained.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
B. Chalmers, H. E. LaBelle Jun.. and A. I. Mlavsky, Mat. Res. Bull 6 (1971) 681.
J. T. A. Pollock, J. Mater. Sci. 7 (1972) 631.
Idem, ibid 7 (1973) 787.
J. T. A. Pollock and J. S. Bailey, ibid 9 (1974) 323.
D. G. Gasson and B. Cockayne, ibid 5 (1970) 100.
J. S. Haggerty, Technical Report NASA CR-120948 (1972).
B. Cockayne, M. Chesswass and D. B. Gasson, J. Mater. Sci. 2 (1967) 7.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Takagi, K., Ishii, M. Crystal growth of sapphire filaments by a laser-heated floating zone technique. J Mater Sci 12, 517–521 (1977). https://doi.org/10.1007/BF00540276
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00540276