Titanium Surface Nitriding by Sodium Amide in Molten Salts

Abstract

A crystalline titanium nitride (TiN) layer on titanium foil is achieved using sodium amide (NaNH₂) as a nitrogen source in LiCl-KCl molten salts. Nanoindentation testing revealed exceptional mechanical properties, with the nitrided surface achieving a hardness of approximately 20.6 GPa, representing more than a four-fold increase compared to the untreated titanium substrate.