A Comparative Study on Microstructure and Properties of FeCoCrNiTi High‐Entropy Alloy Coatings Fabricated by Laser Cladding Under Different Laser Powers

FeCoCrNiTi high‐entropy alloy coatings were laser‐cladded on 40CrNiMo steel at 2.0–3.2 kW. Laser power controlled elemental homogeneity via Marangoni convection and cooling rate. All coatings exhibited dual‐phase FCC + BCC solid solution without intermetallics and a gradient microstructure (cellular, columnar, and equiaxed grains). Hardness and wear resistance first increased and then decreased with power. The optimum at 2.8 kW gave a microhardness of 681.37 HV 0.2 (∼2.5× substrate) and the lowest wear rate (mild abrasive wear). The corrosion resistance of all coatings surpassed the substrate. The 2.8 kW coating showed slightly lower corrosion potential but the highest charge‐transfer resistance, low‐frequency impedance modulus, and widest phase angle plateau, indicating a more compact passive film due to refined grains and homogeneous Ti distribution. This article first reveals the laser power–microstructure–performance chain and clarifies the polarization–impedance contradiction, guiding coating optimization on high‐strength steels.