Effect of absorbed hydrogen on surface nitriding by molten salt electrochemical process

Electrochemical surface nitriding of TiHx electrodes in alpha-, beta-, and delta -phase states were conducted in LiCl-KCl-Li3N melts at 723 K. From X- ray photoelectron spectroscopy and X-ray diffraction analysis of their surf aces, the effect of absorbed hydrogen on the nitriding process was evaluate d. Both atomic ratio of nitrogen and thickness of the formed nitride layer increased considerably for the TiHx electrodes in comparison with the pure titanium electrode. This suggests that the absorbed hydrogen in the titaniu m electrode affects electrochemical nitride formation and accelerates its g rowth. (C) 2000 The Electrochemical Society. S1099-0062(00)04-111-0. All ri ghts reserved.