TY - GEN
T1 - Thermodynamic prediction of compositional phases confirmed by transmission Electron Microscopy on tantalum-based alloy weldments
AU - Moddeman, William E.
AU - Barklay, Chadwick D.
AU - Birkbeck, Janine C.
AU - Miller, Roger G.
AU - Allard, Lawrence F.
AU - Kramer, Daniel P.
PY - 2007
Y1 - 2007
N2 - Tantalum alloys have been used by the U.S. Department of Energy as structural alloys for radioisotope based thermal to electrical power systems since the 1960s. Tantalum alloys are attractive for high temperature structural applications due to their high melting point, excellent formability, good thermal conductivity, good ductility (even at low temperatures), corrosion resistance, and weldability. Tantalum alloys have demonstrated sufficient high-temperature toughness to survive prolonged exposure to the radioisotope power-system working environment. Typically, the fabrication of power systems requires the welding of various components including the structural members made of tantalum alloys. Issues such as thermodynamics, lattice structure, weld pool dynamics, material purity and contamination, and welding atmosphere purity all potentially confound the understanding of the differences between the weldment properties of the different tantalum-based alloys. The objective of this paper is to outline the thermodynamically favorable material phases in tantalum alloys, with and without small amounts of hafnium, during and following solidification, based on the results derived from the FactSage
AB - Tantalum alloys have been used by the U.S. Department of Energy as structural alloys for radioisotope based thermal to electrical power systems since the 1960s. Tantalum alloys are attractive for high temperature structural applications due to their high melting point, excellent formability, good thermal conductivity, good ductility (even at low temperatures), corrosion resistance, and weldability. Tantalum alloys have demonstrated sufficient high-temperature toughness to survive prolonged exposure to the radioisotope power-system working environment. Typically, the fabrication of power systems requires the welding of various components including the structural members made of tantalum alloys. Issues such as thermodynamics, lattice structure, weld pool dynamics, material purity and contamination, and welding atmosphere purity all potentially confound the understanding of the differences between the weldment properties of the different tantalum-based alloys. The objective of this paper is to outline the thermodynamically favorable material phases in tantalum alloys, with and without small amounts of hafnium, during and following solidification, based on the results derived from the FactSage
KW - Hafnium
KW - Tantalum
KW - Welding
UR - http://www.scopus.com/inward/record.url?scp=77958003235&partnerID=8YFLogxK
U2 - 10.1063/1.2437460
DO - 10.1063/1.2437460
M3 - Conference contribution
AN - SCOPUS:77958003235
SN - 9780735403864
T3 - AIP Conference Proceedings
SP - 229
EP - 233
BT - Space Technology and Applications International Forum, STAIF 2007, including Co-located Conferences
T2 - Space Technology and Applications International Forum: Space Renaissance: Inspiring the Next Generation, STAIF-2007
Y2 - 11 February 2007 through 15 February 2007
ER -