Enhanced mechanical and corrosion resistance of TC6 titanium alloy via plasma-nitrided TiN Nitrided layer

Abstract A dense nanocrystalline titanium nitride (TiN) nitrided layer was deposited on TC6 titanium alloy by plasma nitriding to address its low surface hardness and limited corrosion resistance. XRD and SEM analyses confirmed a uniform, compact TiN nitrided layer with high crystallinity and preferred (200) orientation. Nanoindentation revealed markedly higher hardness, modulus, and elastic recovery than the substrate, indicating enhanced wear resistance. Electrochemical tests in 3.5 wt.% NaCl exhibited a higher corrosion potential, reduced current density, and increased charge-transfer resistance, confirming superior corrosion protection. Cavitation erosion tests with electrochemical noise and wavelet analysis further demonstrated stable passivation and resistance to cavitation damage.