IMPROVED CVD BORON FILAMENT PRODUCTION
Final technical rept. 15 Mar 1967-30 Apr 1968
GENERAL ELECTRIC CO PHILADELPHIA PA MISSILE AND SPACE DIV
Pagination or Media Count:
The feasibility of producing CVD Boron filaments using diborane and carbon-coated fused silica glass having valuable specific mechanical properties has been previously on Contract AF 336153268. The purpose of the work reported was to optimize and demonstrate an integrated boron production unit which would incorporate results of the following tests 1 In-line glass monofilament drawing using S-1014 and later GE-177 glass was developed to prepare approximately 1-mil diameter filament at speeds from 50 to 1400 ft. per minute. 2 Various coatings and methods of applying them were considered as a means of providing a conductive coating for resistance or RF heatings. 3 numerous dry contact brushes and wheel-type arrangements were considered as a means of eliminating the mercury contacts that are commonly used in present low-speed reactors. These various dry contacts were not nearly as attractive as RF heating which was then developed to the point where it will not only eliminate all direct contacts with the filament during the processing but appears to offer other advantages. 4 Process and product improvement studies were primarily aimed at improving the deposition rate, tensile strength, and conversion of diborane to boron filament. 5 Automatic Controls were considered to the point where selections can generally be made for usage in the next phase of the program. Additional related topics including preliminary high-speed reactor design, plant layout, and filament costs are also discussed.
- Laminates and Composite Materials
- Fabrication Metallurgy