Surface studies of iridium-alloy grain boundaries associated with weld cracking
Plutonium-238 oxide fuel pellets for the General Purpose Heat Source (GPHS) Radioisotopic Thermoelectric Generators to be used on the NASA Galileo Mission to Jupiter and the International Solar Polar Mission are produced and encapsulated in iridium alloy at the Savannah River Plant (SRP). Underbead cracks occasionally occur in the girth weld on the iridium-alloy-clad vent sets in the region where the gas tungsten arc is quenched. Grain-boundary structures and compositions were characterized by scanning electron microscopy/x-ray energy spectroscopy, electron microprobe analysis and scanning Auger microprobe analysis to determine the cause of weld quench area cracking. Results suggest that weld quench area cracking may be caused by gas porosity or liquation in the grain boundaries.
- Research Organization:
- Du Pont de Nemours (E.I.) and Co., Aiken, SC (USA). Savannah River Lab.
- DOE Contract Number:
- AC09-76SR00001
- OSTI ID:
- 6876797
- Report Number(s):
- DP-MS-82-49; CONF-8210112-1; ON: DE83004919
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
070300* -- Isotopic Power Supplies
36 MATERIALS SCIENCE
360102 -- Metals & Alloys-- Structure & Phase Studies
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ALLOYS
ALPHA DECAY RADIOISOTOPES
CAPSULES
CONTAINERS
CRACKS
CRYSTAL STRUCTURE
ELECTRON MICROSCOPY
ELECTRONIC EQUIPMENT
EQUIPMENT
EVEN-EVEN NUCLEI
GRAIN BOUNDARIES
HEAT SOURCES
HEAVY NUCLEI
IRIDIUM ALLOYS
ISOTOPES
JOINTS
MICROSCOPY
MICROSTRUCTURE
NESDPS Office of Nuclear Energy Space and Defense Power Systems
NUCLEI
PLATINUM METAL ALLOYS
PLUTONIUM 238
PLUTONIUM ISOTOPES
POROSITY
POWER SUPPLIES
QUENCHING
RADIOISOTOPE HEAT SOURCES
RADIOISOTOPES
SCANNING ELECTRON MICROSCOPY
SPACECRAFT POWER SUPPLIES
SPECTROSCOPY
WELDED JOINTS
X-RAY SPECTROSCOPY
YEARS LIVING RADIOISOTOPES