Terminal solid solubility of hydrogen in V–Al solid solution

Hydrogen solubility was studied in vanadium and series of vanadium aluminum alloys at varying temperatures and pressures. The alloys were prepared through aluminothermy followed by electron beam refining and consolidation through vacuum arc melting. The consolidated buttons were hot rolled into 1.2 mm strips. The strips were cut into small pieces. The specimens so obtained were annealed to release the stresses developed during hot-rolling. Hydrogen gas was charged in the specimens at present temperatures and pressures. It was observed that hydrogen solubility decreases linearly with aluminum contents. The decrease in the hydrogen solubility with the aluminum content has been explained on the basis of increase in the Fermi energy level arising from the contribution of electrons by the solute aluminum atom to the valence band of the host matrix vanadium.

► The solubility of hydrogen in vanadium is a function of Fermi level.
► A direct evidence of the explanation is based on the electronic consideration.
► Many intermetalic systems validating the present explanation.
► The present theory complementing the existing theory.