Effect of Hydrogen Absorption on the Electrical Resistance of Melt-Spun Mg-Pd and Mg-Ni-Pd Amorphous Alloys

Abstract

The Mg_100−xPd_x (x = 10, 20 and 30), Mg₈₀Ni_20−yPd_y (y = 5 and 10) and Mg₇₅Ni₂₀Pd₅ amorphous alloys were prepared by the single-roller melt-spinning technique. The electrical resistance was measured during electrochemical hydrogen charging in 6N KOH solution. The Mg₉₀Pd₁₀ amorphous alloy shows larger increase in the electrical resistance by hydrogen absorption than any other alloys prepared in this study. Moreover, the electrical resistance of those alloys was also measured in hydrogen-dissolved water prepared by the bubbling method. As a result, it was found that the electrical resistance increases with increasing immersion time and that the increase amount of the electrical resistance is dependent on the alloy composition. The increase amount of the electrical resistance of the Mg₉₀Pd₁₀ amorphous alloy is much larger than those of other alloys prepared in this work. The increase amount of the electrical resistance of the Mg₉₀Pd₁₀ amorphous alloy after immersion in hydrogen-dissolved water for 300 s is dependent on the concentration of hydrogen in water, and it increases with increasing hydrogen concentration in water. From these results, it is confirmed that hydrogen absorption has a great influence on the electrical resistance of the Mg-based amorphous alloys and that the sensitivity to hydrogen can change largely depending on the alloy composition even in the similar alloy systems.