Abstract:Pd-Ag alloy shows high hydrogen permeability and excellent resistance to hydrogen embrittlement, so it is used to separate the products of methane steam reforming to achieve high purity hydrogen. However, Pd is very expensive; therefore it is eagerly desired to develop no-Pd based alloys with low cost and high hydrogen permeation performance. In order to find out Nb-Ti-Ni alloy with higher hydrogen permeability, the Nb-Ti-Ni alloys located at the straight line connecting the primary (Nb, Ti) of Nb40Ti30Ni30 and the eutectic {(Nb,Ti)+TiNi} phases in the Nb-Ti-Ni trinary diagram were prepared. Results show that the alloys located at the straight line consists of the primary (Nb, Ti) and the eutectic {(Nb,Ti)+TiNi} phases, and their hydrogen permeability increase with increasing of Nb content or volume fraction of the primary (Nb,Ti). Moreover, the Nb content increases to 68 mol%. The Nb68Ti17Ni15 alloy, consisting of 74 vol% primary (Nb, Ti) phase and 26 vol% eutectic {(Nb,Ti)+TiNi} phase, show the highest Φ673K of 4.91′10-8 mol H2m-1s-1Pa-0.5, which is 2.5 times as high as that of the Nb40Ti30Ni30, and 3.5 times as high as that of the pure Pd