Hydrogen diffusivity in B-doped and B-free ordered Ni3Fe alloys

The hydrogen diffusion coefficient of the ordered Ni3Fe–B alloys with and without boron additions was measured by a method of the cathodical precharging with hydrogen. The apparent hydrogen diffusion coefficient decreases with increasing the boron concentration doped in the ordered Ni3Fe alloy. Comparing with the B-free ordered Ni3Fe alloy, the activation energy of hydrogen diffusion for the ordered B-doped Ni3Fe alloy increases by as high as 42% when the boron content is sufficient. The doping boron in the Ni3Fe alloy is effective in reducing the hydrogen diffusion at the grain boundary.