Analysis of the effects of alloying elements on hydrogen solubility in liquid aluminum alloys

Abstract

Reported values of hydrogen solubility in liquid Al-H and Al-H-X (where X = Cu, Si, Zn, Fe, Mg, Ti, or Li) alloys were critically reviewed and analyzed. Plots of log 10 f H X vs. wt.%X revealed that isothermal hydrogen solubility in liquid Al-H-X alloys at 101.3 kPa hydrogen partial pressure decreases with increase in Cu, Si, Zn, and Fe levels, but increases with addition and rising levels of Mg, Li, and Ti. Within the reported temperature and composition ranges, all of the Al-H-X alloys examined in this study are endothermic occluders of hydrogen. That is, hydrogen solubility increases with increase in temperature. The interaction parameters obtained from this study along with those to be obtained from a similar analysis on hydrogen solubility in solid Al-H-X will be useful for an attempt to predict hydrogen solubilities in the more complex, but commercially important, multicomponent aluminum alloys. These values are critical to the understanding of the behavior of hydrogen in aluminum alloys, and to the preservation of the integrity of cast and fabricated aluminum products against the multifarious, and often detrimental, effects of hydrogen.