Recently, refractory alloys have been considered as structural materials for vapor-anode Alkali Metal Thermal-to-Electric Conversion (AMTEC) cells, for extended (7–15 years) space missions. This paper reviewed the existing database for refractory metals and alloys of potential use as structural materials for vapor-anode sodium AMTEC cells. In addition to requiring that the vapor pressure of the material be below 10 −9 torr (133 nPa) at a typical hot side temperature of 1200 K, other screening considerations were: (a) low thermal conductivity, low thermal radiation emissivity, and low linear thermal expansion coefficient; (b) low ductile-to-brittle transition temperature, high yield and rupture strengths and high strength-to-density ratio; and (c) good compatibility with the sodium AMTEC operating environment, including high corrosion resistance to sodium in both the liquid and vapor phases. Nb-1Zr (niobium-1% zirconium) alloy is recommended for the hot end structures of the cell. The niobium alloy C-103, which contains the oxygen gettering elements zirconium and hafnium as well as titanium, is recommended for the colder cell structure. This alloy is stronger and less thermally conductive than Nb-1Zr, and its use in the cell wall reduces parasitic heat losses by conduction to the condenser. The molybdenum alloy Mo-44.5Re (molybdenum-44.5% rhenium) is also recommended as a possible alternative for both structures if known problems with oxygen pick up and embrittlement of the niobium alloys proves to be intractable.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    A review of refractory materials for vapor-anode AMTEC cells


    Contributors:

    Conference:

    SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 2000 ; 2000 ; Albuquerque, New Mexico (USA)


    Published in:

    AIP Conference Proceedings ; 504 , 1 ; 1391-1401


    Publication date :

    2000-01-19


    Size :

    11 pages





    Type of media :

    Conference paper


    Type of material :

    Electronic Resource


    Language :

    English



    A Review of Refractory Materials for Vapor-Anode AMTEC Cells

    King, J. C. / El-Genk, M. S. / University of New Mexico | British Library Conference Proceedings | 2000


    Analysis of a vapor anode, multi-tube, potassium refractory AMTEC converter for space applications

    El-Genk, Mohamed / Tournier, Jean-Michel | American Institute of Physics | 2001


    Analysis of a Vapor Anode, Multi-Tube, Potassium Refractory AMTEC Converter for Space Applications

    El-Genk, M. S. / Tournier, J.-M. / Institute for Space and Nuclear Power Studies | British Library Conference Proceedings | 2001


    Series-Connected Vapor/Vapor AMTEC Cells

    Underwood, Mark L. / Williams, Roger M. / Ryan, Margaret A. et al. | NTRS | 1993


    Performance analysis of a multitube vapor-anode AMTEC cell

    Tournier, J.M. / El-Genk, M.S. / Huang, Lianmin et al. | Tema Archive | 1997