TiO2–ZrO2 composite coatings have attracted significant research interest owing to their potential applications in enhancing the corrosion resistance of marine engineering materials. In this work, TiO2–ZrO2 composite coatings were deposited on 304 stainless steel substrates via radio frequency magnetron sputtering. To ensure methodological rigor, Ti/Zr molar ratios of 2:1, 1:1, and 1:2 were systematically investigated. The effects of the phase structure and surface morphology of different Ti/Zr ratios coatings were systematically investigated. The adhesion strength and mechanical properties of the coatings were evaluated via scratch tests and microhardness measurements, respectively. The corrosion resistance of the optimized coating was evaluated through the static immersion test and electrochemical analysis in a 3.5 wt. % NaCl solution. The results indicated that the coating with a Ti/Zr ratio of 1:1 exhibited a corrosion current density as low as 5.7 × 10−9 A/cm2, a corrosion potential of −0.18 V, and a microhardness of 479 HV, along with excellent adhesion with a critical load of 38 N in scratch tests. Compared with the uncoated 304 stainless steel sample, this coating reduced the corrosion current density by three to four orders of magnitude and shifted the corrosion potential in the positive direction, which indicated a significant improvement in corrosion resistance under chloride-containing environments. After 28 days of the static corrosion testing, the coating surface remained intact and free of cracks, which demonstrated its enhanced long-term corrosion resistance. The TiO2–ZrO2 composite coatings exhibit good corrosion resistance in marine environments, demonstrating considerable application potential for the protection of marine engineering devices.
Zhang et al. (Sun,) studied this question.