Dr. Tetiana Prikhna

Abstract:

Ultrahigh- Amorphous highly conductive coatings Ti-Al-C, (Ti,Mo)-Al-C and (Ti,Cr)-Al-C were deposited on titanium alloy substrates by hybrid magnetron using T₂AlC and Ti₃AlC₂ MAX-phases-based targets and in parallel cathode-arc evaporation of Mo or Cr targets. The (Ti,Cr)-Al-C coating demonstrated the highest long-term oxidation resistance, and after heating in air at 600 °C for 1000 h, its surface electrical conductivity became even slightly higher after long-term heating: increased from s= 9.84×10⁶ S/m to s= 4.35×10⁵ S/m, which is explained by the crystallization of the amorphous coating during heating process. The nanohardness and Young's modulus of the coating after deposition were within 15 GPa and 240 GPa, respectively. The (Ti,Cr)-Al-C coating showed the highest electrochemical corrosion resistance among all deposited coatings in 3.5 wt.% NaCl aqueous solution at 25 °C: corrosion potential E_corr = 0.044 V vs. saturated calomel electrode, corrosion current density i_corr = 2.48×10^-9 A/cm². The hybrid magnetron deposited (Ti,Cr)-Al-C coatings can be used to protect interconnects in lightweight molten carbonate fuel cells elements.