• • The STL6/TiN composite coating achieved a corrosion current density of 0.37 μA/cm², a reduction of at least one order of magnitude compared to the uncoated F347 substrate, directly translating to a lower corrosion rate and extended component lifespan in chloride-rich environments.
• • The passivation potential of the composite coating reached 939 mV, the highest among all tested samples, indicating a more stable and protective passive film that delays breakdown and pitting initiation under anodic polarization.
• • The impedance modulus |Z| of the STL6/TiN coating was the largest, confirming superior barrier properties and charge-transfer resistance, which are critical for maintaining structural integrity in marine or chemical processing applications.
• • Microstructural analysis revealed a defect-free, metallurgically bonded interface with elemental diffusion, and the STL6 layer contained minimal oxides; this ensures strong adhesion and prevents coating spallation, a common failure mode in thermally sprayed coatings.