Abstract:Abstract：In this paper, Microstructure and mechanical performance of Nb-Ti-Ni alloy membranes for hydrogen permeation were investigated. XRD and SEM were employed to characterize the phases and structure of Nb-Ti-Ni alloys, mechanical property of the alloy membrane were measured in Three-point bending tests. The results indicate that as-melt alloy is mainly two-phase structure, consisting of the primary bcc-Nb (Ni,Ti) solid solution phase, (bcc-Nb（Ni, Ti） β2-NiTi) eutectic phase，the first one acts as functional cell for hydrogen permeation, the last one is structural cell to keep the stability of alloy membrane, and good anti-bending properties have been obtained in these samples with net-shape structural region consisting of eutectic phase. Mechanical properties of Nb-Ti-Ni alloy membranes have been inordinately improved by magnetic heat-treatment (MHT) along the three directions (0? 45?and 90?. An obvious improvement have been observed in the case of N7 sample MHT at both of 0?and 45?angle, and the case of N5 sample MHT at 90?angle. MHT can lead to the change of grain sizes and grain orientations, when MHT at 0?angle, tiny bar-like region (consisting of eutectic phase) were formed and spread along the direction of membrane surface, while some oral-like (or spot-like) region were regularly arranged on the surface, and the region extend vertical to the surface in the case of MHT at 90?angle. It is suggested that suitable MHT is good for the improvement of mechanical property of Nb-Ti-Ni alloy membranes.