Investigation of the effect of laser surface treatment on the hot corrosion properties of CSZ/YSZ multilayer TBC coatings

The purpose of the present work is to systematically investigate how laser surface treatment can enhance the ability of advanced thermal barrier coating systems to protect gas turbine substrate materials, focusing on improved phase stability and resistance to hot corrosion through optimized multilayer architectures. Through comprehensive characterization via XRD, SEM, and EDS analyses, we demonstrated that laser treatment markedly enhances coating performance by reducing the monoclinic ZrO₂ phase content by approximately 40%, as a result of rapid solidification (~10⁷ °C/s) and microstructural refinement. The optimized MCrAlY-CSZ-YSZ system with laser modification exhibited superior hot corrosion resistance, enduring 6 cycles compared to only 4 cycles for conventional coatings, attributed to densification (<0.5% porosity) and 46% lower vanadium penetration (9.8 at.% vs 18.1 at.%). The CSZ interlayer played a crucial role by suppressing YVO₄ formation and improving thermal expansion matching. These findings establish laser surface engineering as an effective approach for simultaneously enhancing phase stability and corrosion resistance in TBCs, offering practical solutions for extending turbine component durability in high-temperature corrosive environments. The results provide valuable insights for developing next-generation protective coatings with improved performance characteristics. Thus, the tailored multilayer TBC developed in this study, especially with the inclusion of the CSZ interlayer and laser surface modification, offers superior adhesion, reduced corrosive penetration, and optimized thermal compatibility with the turbine substrate, making it highly suitable for extending the service life of gas turbine components under aggressive operating conditions.