Determination of Activities of Niobium in Cu-Nb Melts Containing Dilute Nb
2015 (English)In: Metallurgical and materials transactions. B, process metallurgy and materials processing science, ISSN 1073-5615, E-ISSN 1543-1916, Vol. 46, no 2, 533-536 p.Article in journal (Refereed) Published
The activity coefficients of niobium in Cu-Nb melts were measured by equilibrating solid NbO2 with liquid copper under controlled oxygen potentials in the temperature range of 1773 K to 1898 K (1500 degrees C to 1625 degrees C). Either CO-CO2 gas mixture or H-2-CO2 gas mixture was employed to obtain the desired oxygen partial pressures. Cu-Nb system was found to follow Henry's law in the composition range studied. The temperature dependence of Henry's constant in the Cu-Nb melts could be expressed as follows: log gamma(0)(Nb(l)) = 3305/T + 0.72. The partial molar excess Gibbs energy change of niobium in Cu-Nb melts can be expressed as follows: Delta(G) over bar (ex)(Nb) = 63,280 + 13.2T(J/mol)
Place, publisher, year, edition, pages
2015. Vol. 46, no 2, 533-536 p.
Metallurgy and Metallic Materials
IdentifiersURN: urn:nbn:se:kth:diva-165205DOI: 10.1007/s11663-015-0312-3ISI: 000351860300001ScopusID: 2-s2.0-84923340980OAI: oai:DiVA.org:kth-165205DiVA: diva2:810501
QC 201505072015-05-072015-04-242015-05-07Bibliographically approved