Pt-modified aluminide coatings are widely used to protect gas turbine hot-section components against high-temperature oxidation and hot corrosion. However, their long-term durability remains a concern under aggressive marine conditions. This work combines machine learning-guided compositional design with experimental investigations of the high-temperature corrosion behavior of Pt-modified aluminide coatings. A Gaussian process regression model was trained on a hot-corrosion dataset compiled from published studies and experimental measurements to establish quantitative correlations among coating composition, test conditions, and corrosion-induced mass change. Based on a multilayer screening strategy, the target Al and Pt concentration ranges were identified, and a β-(Ni, Pt)Al coating with a composition of 48.71Al–3.12Co–2.22Cr–37.11Ni–8.84Pt (at.%) was successfully prepared. The coating exhibited good resistance to NaCl/Na₂SO₄-induced hot corrosion at 900℃. Microstructural characterization revealed the formation of a heterostructure oxide scale, in which the dense inner Al₂O₃ layer effectively inhibited the inward penetration of corrosive species and played a key role in the excellent hot corrosion resistance of the coating.
        Further investigations under high-temperature salt-fog conditions revealed substantially improved corrosion resistance of the β-(Ni, Pt)Al coating compared with the uncoated substrate, with additional improvements achieved through pre-oxidation. At 900℃, coating degradation was dominated by hot corrosion, while the evolution of the surface oxide scale was governed by the competition between oxidation and salt-induced corrosion, resulting in a layered structure consisting of an Al₂O₃-rich outer layer and an underlying nitride-containing inner layer. At 1000℃, scale growth and elemental diffusion became increasingly important in governing coating degradation, suggesting a shift in the dominant corrosion processes with increasing temperature. These results highlight the potential of data-driven compositional design for improving the hot-corrosion resistance of Pt-modified aluminide coatings and provide insights into their degradation mechanisms in marine environments.