In this study, an Inconel625-Ni60-Ni60/25%WC (Inconel625-Ni/WC) composite coating was fabricated on Cr12MoV steel by first-stage laser cladding, followed by second-stage laser remelting with various laser powers, and the better laser energy density of 25.0 J/mm² for laser remelting test was obtained by macroscopic morphology and microhardness analysis. The effects of laser remelting on the microstructure, microhardness, wear resistance, and impact resistance of the composite coating was systematically investigated by combining various characterization methods. The results showed that laser remelting did not cause the composite coating to produce new phases. The microstructure of the Ni/WC layer in the remelted composite coating was denser and finer, and the average grain size of the surface layer was reduced by 11.69%. The impact depth of laser remelting was about 2.0 mm. The average microhardness of the Ni/WC layer in the remelted composite coating increased by 5.9%, and the average wear rate of the surface was reduced by 50.12% compared with that before laser remelting. The wear surface of remelted composite coating exhibited abrasive wear, and the wear resistance was significantly improved. In addition, the impact toughness value of the remelted composite coating reached 5.15 J/cm², which increased by 87.96% compared with that before laser remelting. The impact resistance of the composite coating was further improved.

In order to achieve high-performance coatings on the surface of electric submersible pump impellers, it is crucial to optimize the laser cladding process parameters. Using Ansys 2021 R1 commercial software, a numerical simulation of laser cladding Ni60 powder on high nickel cast iron was conducted. The simulation utilized a 3D Gaussian heat source, parametric language, and life–death unit technology to replicate the characteristics of synchronous powder delivery laser cladding. The study focused on analyzing the temperature field cloud map and molten pool size under different laser power and scanning speeds, narrowing down the process parameter window, selecting optimized laser power and scanning speed, and assessing the changes in surface morphology, melting height and width, dilution rate, microhardness, and microstructure of the laser cladding coating. Results indicate that the coating width and thickness increase with higher laser power and lower scanning speeds. The microstructure consists primarily of dendritic, block, short rod, and long strip formations, and exhibits a tightly distributed and uniform grain structure. Furthermore, the microhardness of the coating shows a negative correlation with laser power and scanning speed. The optimal process parameters were determined to be a laser power of 1100 W and a scanning speed of 6 mm/s. A comparison with the simulation confirmed the effectiveness of the simulation in effectively guiding actual production.