OXIDATION RESISTANT HIGH TEMPERATURE PROTECTIVE COATINGS FOR TUNGSTEN. Sixth Quarterly Progress Report, August 1, 1962 TO October 31, 1962

Technical Report · Thu Oct 31 04:00:00 EST 1963

OSTI ID:4751023

A method was found to apply the Ti-Zr-(Si-W)-O complex coating to tungsten sheet and eliminate the deleterious crust layer formation previously encountered. The exact nature of the crust formation was not completely established but its formation can be controlled and eliminated. Cyclic oxidation tests at 3450 deg F were conducted on the W + Ti -Zr --(Si --W) -O system with and without the crust formation. Maximum life at 3450 deg F for the system free of crust was 17.5 hours while the system containing various amounts of the crust layer failed within 2 to 3 hours. Other factors affecting the ultimate capability of this coating system at elevated temperatures, previously masked by the crust layer-coating reaction, were identified and discussed. Cyclic oxidation tests on the W + (Si --W) --O and W + Ti -- Zr - (Si - W) --O (without crust formation) systems were conducted at 1600, 1800, and 2500 deg F. Oxidation tests at 3000 deg F were carried out on the W + (Si--W) --O and W + Ti -- Zr -- (Si --W) -- O systems with partial crust layers. Weight change as a function of time at this temperature was determined for periods up to and slightly exceeding 4 hours for each system and representative curves are presented. X-ray- diffraction patterns of the W + Si and W + (Si --W) systems in the as coated and exposed condition were made. Operation of the high temperature furnace for extended periods of time at 3450 deg F with atmosphere control of the test zone is described. (auth)

• Research Organization: TAPCO. Div. of Thompson Ramo Wooldridge Inc., Cleveland
• NSA Number: NSA-17-006519
• OSTI ID: 4751023
• Report Number(s): NP-12293; TM-3543-67
• Country of Publication: United States
• Language: English

Related Subjects

COATING
CORROSION PROTECTION
DIAGRAMS
DIFFRACTION
HIGH TEMPERATURE
LAYERS
MATERIALS TESTING
METALS, CERAMICS, AND OTHER MATERIALS
OXIDATION
OXIDES
SILICIDES
TEMPERATURE
TITANIUM COMPOUNDS
TUNGSTEN
TUNGSTEN COMPOUNDS
WEIGHT
X RADIATION
ZIRCONIUM COMPOUNDS