Electrochemical and Corrosion Behavior of Nanocrystalline TiNi-Based Alloys and Composite

In this work TiNi-based nanocrystalline alloys and composite were produced by mechanical alloying process with subsequent annealing at 750°C for 0.5 h. Mechanical alloying was performed in a SPEX 8000 Mixer Mill. TiNi alloy was chemically modified by Ag elemental powder. Silver content equaled 5 wt%. X-ray diffraction analyses revealed formation of TiNi main phase after annealing. Additionally, two minor phases $Ti_2Ni$ and $TiNi_3$ were detected for unmodified alloy. Crystallites of obtained powders were nanosized. Corrosion and electrochemical measurements were performed in 6 M KOH solution. All synthesized materials were used as negative electrode for $Ni-MH_x$ batteries. Ag addition positively affects on stability of discharge capacity of TiNi alloy during of charge/discharge tests.