Process parameter optimization of Fe-based coating on ductile iron using laser cladding with grey related analysis

Owing to the laser cladding process for substantial damage in dust cast iron, this study systematically investigated the Fe-based single-track laser modification process for ductile cast iron, aiming to reduce the damage to ductile iron during laser cladding (LC). The three parameters, laser power (P), scanning speed (V) and powder feeding rate (F) were optimized by employing the Taguchi-grey correlation method. A Taguchi-designed orthogonal experiment was conducted focused on cladding width, cladding height, and dilution rate as the response targets. Insights into the impact of process parameters on geometric characteristics were provided by contour plots, surface plots, and Signal-to-Noise Ratio (S/N) analysis. With the grey relational theory, the three response targets were transformed into a single Grey Relational Grade (GRG) value, quantifying the optimization for maximum cladding width (W), cladding height (H), and appropriate dilution rate (D). Additionally, the results indicated the improvements in the three response targets, discussing the optimized cladding layer’s advantage in morphology and microstructure compared to other layers. This study provides the theoretical feasibility of laser cladded Fe-based powders for laser cladded cast iron.