Mass spectrometric studies of alloys proposed for high temperature reactor systems. II

The vaporization of the alloys inconel 617 and nimonic PE 13 was studied by high-temperature mass spectrometry. This is of particular interest for the use of these alloys in advanced gas-cooled high temperature reactors and thermonuclear fusion devices. Therefore, the partial pressures of nickel, chromium (1355-1527 K) and cobalt (1214-1517 K) over inconel 617 as well as of nickel, chromium, iron (1349 to 1493 K) and cobalt (1279 to 1500 K) over nimonic PE 13 were determined in the given temperature ranges. Chemical activities, partial free energies of mixing and excess partial free energies of the alloy components were computed from the partial pressures. The thermodynamic functions obtained are discussed. (Auth.)