Accession Number : AD0436294


Title :   ALKALI METAL RESISTANT WIRE,


Corporate Author : WESTINGHOUSE ELECTRIC CORP LIMA OHIO


Personal Author(s) : Bober,E S ; Stapleton,R E ; Snavely,W H


Report Date : 15 Apr 1964


Pagination or Media Count : 163


Abstract : A ceramic coated conductor system was developed that was unaffected by 172 hours exposure to K (potassium) vapor at 850 C. This system was Metco 201 Zirconia, plasma sprayed on nickel aluminide coated Nickel clad Silver AWG 8 (Sylvania) wire. This system, however, is not suitable for electrical operation at 850 C since the resistance of the zirconia coating drops to about 5 ohms at 600 C. Overcoating the zirconia with aluminum nitride by a vapor plating technique results in a resistance at 850 C in argon for the multicoat of 1.8 x 10 to the 4th power ohms. The aluminum nitride overcoated zirconia is unaffected by 172 hours exposure. A number of high purity insulators were found to be resistant to potassium vapor at 850 C. These were alumina, magnesia, and strontium zirconate.a primary problem with plasma spray coatings of these materials is loss of adhesion in the potassium vapor even when a nickel aluminide undercoat is used. (Author)


Descriptors :   *ELECTRIC WIRE , *ELECTRICAL INSULATION , *WIRE , ALKALI METALS , CERAMIC COATINGS , SILVER , HIGH TEMPERATURE , VAPORS , POTASSIUM , ALUMINUM COMPOUNDS , NICKEL COMPOUNDS , ZIRCONIUM COMPOUNDS , OXIDES , VAPOR PLATING , ADHESION , DAMAGE , RADIATION EFFECTS , GAMMA RAYS , THERMAL RADIATION , STRONTIUM COMPOUNDS , ZIRCONATES , NICKEL , METAL COATINGS , MERCURY , NITRIDES , BORON COMPOUNDS , VIBRATION , SHOCK RESISTANCE , COPPER , METAL SEALS , TUNGSTEN


Distribution Statement : APPROVED FOR PUBLIC RELEASE