HALOGEN ADDITIONS TO INERT-ATMOSPHERE WELD CHAMBERS

Technical Report · Sun May 01 04:00:00 EDT 1960

OSTI ID:4147131

Matchett, R L; Frankhouser, W L

Halogen gas addition to an argon atmosphere in a chamber used for tungsten-arc welding of Zircaloy-2 and -3 clad nuclear fuel assemblies was investigated. Freon-12 at a concentration of 0.5 vol.% was selected from a group of five halogen gases as the standard addition. The typical weld depth-to-width ratio for vacuum-melted Zircaloy-2 welded in argon was changed from 1-to-4 to 1-to-2 by the addition of Freon-12. However, the tungsten electrode was attacked and the point shape converted to a spherical configuration. This caused the are to become directionally unstable, resulting in wide variations in weld penetration. The chamber atmosphere was clouded with a smoke-lixe reaction product, which was filtered from the atmosphere in a recycle loop attached to the weld chamber. Heat inputs, at equal welding speeds, to achieve 100% penetration ity and produce ductile joints with a number of heatresisting alloys, without reacting excessively with them. Low-melting nickel--palladium base brazing alloys, containing beryllium and/or silicon, were developed. The most promising alloy, containing 0.25% Re, 0.49% Si, 44.3% Ni, and 54.96% Pd, has a melting range of 2040 to 2120 deg F, is workable into thin strip stock, produces superior wetting of Ti and/or Al bearing high-temperature alloys, causes little base-metal penetration or erosion during brazing of thin-walled wrought metals, has adequate shear strength to 1500 deg F, and exkibits roomtemperature ductility in brazed joints of various base metals. (B.O.G.)

• Research Organization: Westinghouse Electric Corp. Bettis Atomic Power Lab., Pittsburgh
• DOE Contract Number: AT(11-1)-GEN-14
• NSA Number: NSA-14-018150
• OSTI ID: 4147131
• Report Number(s): WAPD-223
• Country of Publication: United States
• Language: English

Related Subjects

CHEMICAL REACTIONS
CONFIGURATION
DEFECTS
DIFFUSION
ELECTRIC ARCS
ELECTRODES
FILTERS
FREONS
FUEL CANS
HALOGENS
HEATING
INERT GASES
MACHINE PARTS
MELTING
METALS, CERAMICS, AND OTHER MATERIALS
QUANTITY RATIO
SPHERES
STABILITY
STANDARDS
THICKNESS
TUNGSTEN
VACUUM
VARIATIONS
VELOCITY
VOLUME
WELDING
ZIRCALOY