Radioisotope space power generator. Annual report, October 1978-September 1979

Technical Report · Mon Mar 01 00:00:00 EST 1982

DOI:https://doi.org/10.2172/5462119· OSTI ID:5462119

Elsner, N B; Chin, J; Staley, H G; Bass, J C; Morris, C C; Shearer, C H; Steeger, E J

The emphasis of the Isotec Technology Program shifted from development of a Galileo generator to study of a segmented selenide element and couple technology. The goal of the FY 79 program was to determine the feasibility of fabricating segmented selenide P and N elements which exploit the high thermoelectric efficiency of (Cu,Ag)/sub 2/Se and Gd/sub 2/Se/sub 3/ materials. A preliminary evaluation of segmented element efficiencies, material compatibilities, and fabrication abilities was used to select (Cu,Ag)/sub 2/Se/Fe(Bi,Sb)/sub 2/Te/sub 3/ for the P element and Gd/sub 2/Se/sub 3//PbTe for the N element. The iron barrier between the (Cu,Ag)/sub 2/Se and (Bi,Sb)/sub 2/Te/sub 3/ prevented degradation of thermoelectric properties from copper contamination of the (Bi,Sb)/sub 2/Te/sub 3/. Fabrication processes for both elements were developed. Gd/sub 2/Se/sub 3/ was friable and difficult to fabricate crack-free. It also exhibited a phase transition from cubic to orthorhombic, which increased its susceptibility to microcracking and reduced its thermoelectric efficiency. Life testing of an all-bonded couple with unsegmented (Cu,Ag)/sub 2/Se P-type and Gd/sub 2/Se/sub 3/ N-type elements was stopped after 3300 h in a nominal 830/sup 0/C/390/sup 0/C thermal gradient. The Gd/sub 2/Se/sub 3/ leg did not show any significant degradation during the test. Examination of the hot end of the P element showed the need for a less reactive hot cap material and an improved vapor supression system. Module testing of a 1-W (Bi,Sb)/sub 2/(Se,Te)/sub 3/ generator was performed for 5000 h with no degradation in power. High-temperature Thermid 600 adhesive curing cycles were examined, 75-mW module loading tests were performed, and diagnostic examination of RTG-2A and RTG-201 was completed.

• Research Organization: General Atomics, San Diego, CA (United States)
• DOE Contract Number: AT03-76SF70060
• OSTI ID: 5462119
• Report Number(s): GA-A-16233; ON: DE84005675
• Country of Publication: United States
• Language: English

Related Subjects

07 ISOTOPES AND RADIATION SOURCES
RADIOISOTOPE GENERATORS
FABRICATION
SPACECRAFT POWER SUPPLIES
THERMOELECTRIC GENERATORS
ADHESIVES
ANTIMONY TELLURIDES
BISMUTH TELLURIDES
COPPER SELENIDES
CRACKS
CURING
GADOLINIUM SELENIDES
PHASE TRANSFORMATIONS
SILVER SELENIDES
THERMAL DEGRADATION
ANTIMONY COMPOUNDS
BISMUTH COMPOUNDS
CHALCOGENIDES
COPPER COMPOUNDS
DIRECT ENERGY CONVERTERS
ELECTRONIC EQUIPMENT
EQUIPMENT
GADOLINIUM COMPOUNDS
POWER SUPPLIES
RARE EARTH COMPOUNDS
SELENIDES
SELENIUM COMPOUNDS
SILVER COMPOUNDS
TELLURIDES
TELLURIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
NESDPS Office of Nuclear Energy Space and Defense Power Systems
070301* - Isotopic Power Supplies- Design & Fabrication- (-1987)