Effects of Mo alloying on the structure and hydrogen-permeation properties of Nb metal

Effects of alloying Nb with Mo on the structure and hydrogen permeation properties of Nb metal have been investigated by XRD analysis, PCT measurements, and three-point bending tests. The results indicate that all the as-prepared Nb100-xMox (x = 2, 7, 14) alloy samples are Nb-based solid solutions with a BCC structure, which are hydrogenated into their corresponding hydrides with the NbH0.95 phase after interaction with hydrogen. The lattice deformations of the BCC structure and NbH0.95 phase are due to the difference in size between Nb and Mo atoms. The Nb86Mo14 sample has a higher hydrogen-diffusion coefficient value (1.84 × 10−9 cm/s), higher hydride-formation enthalpies (- 35.8 kJ/(mol·H2)) with the maximum force and displacement before/after the hydrotreatment, indicating that alloying with Mo can greatly improve the hydrogen-diffusion behavior and anti-bending properties of Nb metal.