Thermal stability of Ni40Ti40Nb20 and Ni32Ti48Nb20 tapes obtained by rapid solidification technique

摘要

Nickel-titanium-group 5A metal (V, Nb, Ta, Zr) alloys are known as promising hydrogen-selective membrane materials. They can potentially be used in membrane reactors, which can produce high-purity H _2 and CO _2 streams from coal-derived syngas at elevated temperatures. The master alloys were prepared by arc melting using high purity metals in a Ti-gettered argon atmosphere. The alloys were melted several times in order to improve homogeneity. The ingots were induction-melted under a high-purity argon atmosphere in a quartz tube and graphite crucible injected through a nozzle onto a Cu wheel to produce rapidly solidified amorphous ribbons. Thermal stability of the Ni40Ti40Nb20 and Ni32Ti48Nb20 thin tapes has been examined using DTA analysis.