<p>Laser cladding coatings have emerged as a promising solution for mitigating high-temperature corrosion failures in waste incineration boiler components. However, their protective efficacy is often compromised by elemental segregation and surface defect. To address these limitations, this study employs an innovative high-speed laser cladding coupled with laser remelting composite technique to fabricate Inconel 625 (IN625) alloy coatings. The high-temperature corrosion behavior was systematically investigated through exposure to a mixed salt environment (33% NaCl + 31% KCl + 9% Na₂SO₄ + 27% K₂SO₄) at 600&#xa0;°C. Corrosion kinetics were quantitatively assessed via mass loss per unit area measurements. Comprehensive microstructural characterization and phase element composition were performed using scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) and x-ray diffraction (XRD) analysis. The results reveal that laser remelting with optimized parameters (1500W power) effectively eliminates elemental segregation while promoting the formation of a continuous Cr₂O₃-rich layer. This dual mechanism significantly enhances corrosion resistance by inhibiting molten salt penetration through: microstructural densification reducing diffusion pathways, and chromium redistribution facilitating protective oxide formation. The IN625 coating demonstrates approximate 40% lower corrosion rates compared to conventional laser-cladded counterparts, offering substantial improvements in coating durability for extreme thermal corrosion environments.</p>