Influence of Al addition on microstructure and properties of Cu-Fe-based coatings by laser induction hybrid rapid cladding

To establish the relationships between composition, microstructure, and properties, the influence of Al addition on microstructure and properties of Cu-Fe-based coatings by laser induction hybrid rapid cladding was studied. With increasing Al content, the main diffraction peaks of epsilon-Cu phase are weakened but those of alpha-Fe phase are strengthened, the size of Fe-rich particles generally increases but the dendrite arm spacing is further reduced, and the number of Cu-rich grains precipitated inside the Fe-rich particles increases but the size reduces. Moreover, when the amount of Al is increased, the improvement in electrochemical resistance is attributed to large amounts of fine Cu-rich grains precipitated inside the Fe-rich particles, which results in large anode-small cathode effect. The microhardness also increases with Al content and the microhardness of Cu53.5Fe36Al10C0.5 coating is approximately 2.4 times higher than that of copper alloy substrate.