ADVANCEMENT OF HIGH TEMPERATURE PROTECTIVE COATINGS FOR COLUMBIUM ALLOYS. First Interim Technical Progress Report Covering Period October 16, 1961 to February 16, 1962

Technical Report · Wed Oct 31 04:00:00 EST 1962

OSTI ID:4792999

Modifications in the Cr-Ti-Si vacuum vapor coating process were made which resulted in a reduction in the time, temperature, and vacuum requirements for the overall process. The most promising processing parameters established involved the co-deposition of Cr-Ti in 8 hours at 2200 deg F, followed by alloying with Si in 4 hours at 2000 deg F at an operating pressure of 10/sup -2/ mm. Oxidation protective life data is presented for the Cr-Ti-Si coating on Nb base materials at 1200 to 3000 deg F. Protection is provided for several hundred hours at temperatures up to 2300 deg F, in excess of 100 hours at 2500 deg F, and 2 to 8 hours at 3000 deg F. Further investigation was conducted to determine the most effective halide activators for each step in the formation of the Cr-Ti-Si coating under conditions where continuous evacuation was not employed. Metallographic analyses and cyclic oxidation tests at 2500 deg F were used to evaluate the various systems produced by the activator-reduced pressure modification in the coating process. (auth)

• Research Organization: TAPCO. Div. of Thompson Ramo Wooldridge Inc., Cleveland
• NSA Number: NSA-16-015125
• OSTI ID: 4792999
• Report Number(s): NP-11483; TM-3332-67
• Country of Publication: United States
• Language: English

Related Subjects

ACTIVATION
CHROMIUM ALLOYS
COATING
HALIDES
HIGH TEMPERATURE
MATERIALS TESTING
METALLOGRAPHY
METALS, CERAMICS, AND OTHER MATERIALS
NIOBIUM ALLOYS
OXIDATION
SILICIDES
STABILITY
TITANIUM ALLOYS
VACUUM
VAPORS