Weld repair of helium degraded reactor vessel material

Conference · Mon Jan 01 04:00:00 EST 1990

OSTI ID:5582986

Kanne, Jr, W R; Lohmeier, D A; Louthan, Jr, M R; Rankin, D T; Franco-Ferreira, E A ^[1]; Bruck, G J; Madeyski, A; Shogan, R P; Lessmann, G G ^[2]

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1. Westinghouse Savannah River Co., Aiken, SC (United States)
2. Westinghouse Electric Corp., Pittsburgh, PA (United States). Science and Technology Center

Welding methods for modification or repair of irradiated nuclear reactor vessels are being evaluated at the Savannah River Site. A low-penetration weld overlay technique has been developed to minimize the adverse effects of irradiation induced helium on the weldability of metals and alloys. This technique was successfully applied to Type 304 stainless steel test plates that contained 3 to 220 appm helium from tritium decay. Conventional welding practices caused significant cracking and degradation in the test plates. Optical microscopy of weld surfaces and cross sections showed that large surface toe cracks formed around conventional welds in the test plates but did not form around overlay welds. Scattered incipient underbead cracks (grain boundary separations) were associated with both conventional and overlay test welds. Tensile and bend tests were used to assess the effect of base metal helium content on the mechanical integrity of the low-penetration overlay welds. The axis of tensile specimens was perpendicular to the weld-base metal interface. Tensile specimens were machined after studs were resistance welded to overlay surfaces.

• Research Organization: Westinghouse Savannah River Co., Aiken, SC (United States)
• Sponsoring Organization: DOE; USDOE, Washington, DC (United States)
• DOE Contract Number: AC09-89SR18035
• OSTI ID: 5582986
• Report Number(s): WSRC-MS-90-298; CONF-910808--9; ON: DE92011174
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
220200* -- Nuclear Reactor Technology-- Components & Accessories
36 MATERIALS SCIENCE
360103 -- Metals & Alloys-- Mechanical Properties
360106 -- Metals & Alloys-- Radiation Effects
ALLOYS
AUSTENITIC STEELS
CHROMIUM ALLOYS
CHROMIUM-NICKEL STEELS
CONTAINERS
CORROSION RESISTANT ALLOYS
CRACKS
CRYSTAL STRUCTURE
EMBRITTLEMENT
GRAIN BOUNDARIES
HEAT AFFECTED ZONE
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
HELIUM EMBRITTLEMENT
HIGH ALLOY STEELS
IRON ALLOYS
IRON BASE ALLOYS
JOINTS
MATERIALS
MECHANICAL PROPERTIES
MICROSTRUCTURE
NICKEL ALLOYS
REACTOR VESSELS
STAINLESS STEEL-304
STAINLESS STEELS
STEEL-CR19NI10
STEELS
STRESSES
TENSILE PROPERTIES
THERMAL STRESSES
WELDED JOINTS
ZONES