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Title: High Temperature Stability of Dissimilar Metal Joints in Fission Surface Power Systems

Abstract

Future generations of power systems for spacecraft and lunar surface systems will likely require a strong dependence on nuclear power. The design of a space nuclear power plant involves integrating together major subsystems with varying material requirements. Refractory alloys are repeatedly considered for major structural components in space power reactor designs because refractory alloys retain their strength at higher temperatures than other classes of metals. The relatively higher mass and lower ductility of the refractory alloys make them less attractive for lower temperature subsystems in the power plant such as the power conversion system. The power conversion system would consist more likely of intermediate temperature Ni-based superalloys. One of many unanswered questions about the use of refractory alloys in a space power plant is how to transition from the use of the structural refractory alloy to more traditional structural alloys. Because deleterious phases can form when complex alloys are joined and operated at elevated temperatures, dissimilar material diffusion analyses of refractory alloys and superalloys are needed to inform designers about options of joint temperature and operational lifetime. Combinations of four superalloys and six refractory alloys were bonded and annealed at 1150 K and 1300 K to examine diffusional interactions inmore » this study. Joints formed through hot pressing and hot isostatic pressing were compared. Results on newer alloys compared favorably to historical data. Diffusional stability is promising for some combinations of Mo-Re alloys and superalloys at 1150 K, but it appears that lower joint temperatures would be required for other refractory alloy couples.« less

Authors:
 [1]; ; ;  [2]
  1. University of Toledo at NASA Glenn Research Center at Lewis Field, Cleveland, OH 44135 (United States)
  2. NASA Glenn Research Center at Lewis Field, Cleveland, OH 44135 (United States)
Publication Date:
OSTI Identifier:
21054561
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 880; Journal Issue: 1; Conference: International forum-STAIF 2007: 11. conference on thermophysics applications in microgravity; 24. symposium on space nuclear power and propulsion; 5. conference on human/robotic technology and the vision for space exploration; 5. symposium on space colonization; 4. symposium on new frontiers and future concepts, Albuquerque, NM (United States), 11-15 Feb 2007; Other Information: DOI: 10.1063/1.2437505; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANNEALING; DIFFUSION; DUCTILITY; FISSION; HEAT RESISTING ALLOYS; HOT PRESSING; JOINTS; LIFETIME; METALS; MOLYBDENUM ALLOYS; POWER SYSTEMS; REACTOR MATERIALS; REFRACTORIES; RHENIUM ALLOYS; SPACE POWER REACTORS; STABILITY; NESDPS Office of Nuclear Energy Space and Defense Power Systems

Citation Formats

Locci, Ivan E., Nesbitt, James A., Ritzert, Frank J., and Bowman, Cheryl L.. High Temperature Stability of Dissimilar Metal Joints in Fission Surface Power Systems. United States: N. p., 2007. Web. doi:10.1063/1.2437505.
Locci, Ivan E., Nesbitt, James A., Ritzert, Frank J., & Bowman, Cheryl L.. High Temperature Stability of Dissimilar Metal Joints in Fission Surface Power Systems. United States. doi:10.1063/1.2437505.
Locci, Ivan E., Nesbitt, James A., Ritzert, Frank J., and Bowman, Cheryl L.. Tue . "High Temperature Stability of Dissimilar Metal Joints in Fission Surface Power Systems". United States. doi:10.1063/1.2437505.
@article{osti_21054561,
title = {High Temperature Stability of Dissimilar Metal Joints in Fission Surface Power Systems},
author = {Locci, Ivan E. and Nesbitt, James A. and Ritzert, Frank J. and Bowman, Cheryl L.},
abstractNote = {Future generations of power systems for spacecraft and lunar surface systems will likely require a strong dependence on nuclear power. The design of a space nuclear power plant involves integrating together major subsystems with varying material requirements. Refractory alloys are repeatedly considered for major structural components in space power reactor designs because refractory alloys retain their strength at higher temperatures than other classes of metals. The relatively higher mass and lower ductility of the refractory alloys make them less attractive for lower temperature subsystems in the power plant such as the power conversion system. The power conversion system would consist more likely of intermediate temperature Ni-based superalloys. One of many unanswered questions about the use of refractory alloys in a space power plant is how to transition from the use of the structural refractory alloy to more traditional structural alloys. Because deleterious phases can form when complex alloys are joined and operated at elevated temperatures, dissimilar material diffusion analyses of refractory alloys and superalloys are needed to inform designers about options of joint temperature and operational lifetime. Combinations of four superalloys and six refractory alloys were bonded and annealed at 1150 K and 1300 K to examine diffusional interactions in this study. Joints formed through hot pressing and hot isostatic pressing were compared. Results on newer alloys compared favorably to historical data. Diffusional stability is promising for some combinations of Mo-Re alloys and superalloys at 1150 K, but it appears that lower joint temperatures would be required for other refractory alloy couples.},
doi = {10.1063/1.2437505},
journal = {AIP Conference Proceedings},
number = 1,
volume = 880,
place = {United States},
year = {Tue Jan 30 00:00:00 EST 2007},
month = {Tue Jan 30 00:00:00 EST 2007}
}
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