Accession Number:

ADA113614

Title:

Manufacturing Methods and Technology Engineering for Growth of Large Diameter Nd: YAG Laser Crystals

Descriptive Note:

Final rept. 1 Oct 1979-1 Apr 1980

Corporate Author:

LITTON SYSTEMS INC MORRIS PLAINS NJ AIRTRON DIV

Personal Author(s):

Report Date:

1980-07-01

Pagination or Media Count:

35.0

Abstract:

This report describes initial experiments on the growth of two inch diameter NdYAG laser crystal boules by the Czochralski method. Power was supplied through a 450 kHz, 120 kVA, RF generator to heat a 4.5x4.5 inch cylindrical iridium crucible. Melt charges of 4.3 kg were employed which contained a 1.1 atomic percent of Nd. The first few runs presented difficulties in enlarging the seed crystal to the finished diameter. Most boules were strained highly and cracked spontaneously. A technique of gradual enlargement of the seed worked more satisfactorily and allowed short sections of two inch boules to be grown. Cracking of boules is related to blossom formation after seeding and is connected with large radial gradients in the melt. Measurements were made to define and minimize these gradient for increased chances of large boule growth. Seven growth runs were completed this period but no suitable material for rods was obtained.

Subject Categories:

  • Lasers and Masers
  • Fabrication Metallurgy
  • Crystallography

Distribution Statement:

APPROVED FOR PUBLIC RELEASE