Vacuum thermal dealloying of magnesium-based alloys for fabrication of nanoporous refractory metals

A specialized dealloying technique called thermal dealloying was developed over 10 years ago for certain biomedical materials. This method is not widely used for synthesizing nanoporous metals. However, it offers advantages over conventional dealloying processes for fabrication of nanoporous structures, and is highly suitable for refractory metals that may be susceptible to oxidation during chemical/electrochemical dealloying and liquid metal dealloying. In this study, nanoporous structures were successfully fabricated from magnesium-based precursor alloys via sublimation of magnesium at elevated temperature under vacuum conditions. Different refractory metal diffusion rates affect the resulting density and amount of retained magnesium in each nanoporous material.