Accession Number:

AD0810272

Title:

GENERATOR DEVELOPMENT, SPUR PROGRAM. PART II. GENERATOR STATOR BORE-SEAL.

Descriptive Note:

Technical rept. 1 Apr 63-1 Nov 66,

Corporate Author:

WESTINGHOUSE ELECTRIC CORP LIMA OH AEROSPACE ELECTRICAL DIV

Personal Author(s):

• Hoop, John G.

Report Date:

1967-02-01

Pagination or Media Count:

55.0

Abstract:

The tubular ceramic-metal bore-seal for protection of electrical windings in the stator of the hermetically sealed alkali-metal Rankine cycle SNAP-50SPUR electric turbogenerator must have a life of more than 10,000-hours in potassium vapor at a temperature of 900 F. A preceding report, ASD-TDR-63-677, Part I, gave the results of early developments and short-time testing of materials. This Part II of the report describes the effect of long-time potassium exposure and the initial trials in brazing 11.5-inch diameter tubular specimens. Testing demonstrated that several brazement combinations with 99-percent alumina and 99Cb1Zr alloy members can resist potassium vapor attack for the required 10,000-hour service time at 900 F. However, the 75Zr19Cb6Be brazing alloy produced strong potassium resistant joints and also gave the best results in producing vacuum-tight ceramic-metal joints with the slow brazing cycles needed for fabrication of large assemblies.

Descriptors:

• *HERMETIC SEALS
• GENERATORS
• NUCLEAR POWER PLANTS
• METALS
• ALUMINATES
• BRAZING
• CERAMIC MATERIALS
• NIOBIUM
• POTASSIUM
• BRAZING ALLOYS

Subject Categories:

• Adhesives, Seals and Binders

Distribution Statement:

APPROVED FOR PUBLIC RELEASE