Enhanced tribological performance of laser-cladded In718 coatings: Cladding parameters optimization via thermo-mechanical simulation

Cladding high-hardness In718 alloy onto ductile iron emerges as an effective solution to mitigate interfacial degradation, owing to the alloy’s superior resistance to corrosion, oxidation, wear and thermal fatigue. Herein, the effects of laser cladding parameters on the tribological performance of laser-cladded In718 coatings were investigated. Simulation results demonstrated that optimized cladding parameters effectively homogenize the molten pool’s temperature gradient and significantly reduce the residual stress within the cladding layer, thereby enhancing the cladding quality. In718 alloy coatings were cladded on ductile iron substrates using simulation-optimized cladding parameters, achieving a microcrack-free morphology with minimal powder inclusions, negligible pores, and refined metallographic structures. The coatings demonstrate a substantial hardness enhancement of 46.7%–58.9% compared to the substrate, attributed to hard carbide formation and metallurgical grain refinement. The coatings generate a stable coefficient of friction across varying loads, with values of 0.63–0.77 (10 N), 0.58–0.77 (12 N) and 0.63–0.72 (15 N), demonstrating enhanced hardness and wear resistance. The wear severity of the coatings exhibits minimal variation, but intensifies remarkably with increasing loads. The dominant wear mechanisms include abrasive wear, fatigue wear and plastic deformation, with oxidative wear becoming a significant factor under higher loads. This study provides a technical foundation for developing high-hardness In718 alloy coatings with enhanced tribological performance.