| Summary: | The Inconel 718 alloy clad coating was successfully prepared via pulsed laser deposition. The effect of pulse frequency on the evolution of microstructure, hardness and tribological properties of the as-deposited samples were analyzed via scanning electron microscopy (SEM), microhardness tester and ball-on-plate tribometer. The results showed that with the decrease in pulse frequency, the cooling rate of molten pool increases gradually, which effectively refines the γ-(Ni, Cr, and Fe) dendrites and restrains Nb segregation. Hence, the morphology of the brittle Laves phase changed from long chained to granular and its volume fraction decreased from 6.59% to 2.41%. The hardness of the coating increased from 261 HV<sub>0.1</sub> to 297 HV<sub>0.1</sub> and the tribological property also improved simultaneously. The friction coefficient decreased from 0.2387 to 0.2066, and the wear rate decreased from 27.30 × 10<sup>−4</sup> mg·N<sup>−1</sup>·m<sup>−1</sup> to 19.15 × 10<sup>−4</sup> mg·N<sup>−1</sup>·m<sup>−1</sup>. It can also be observed that the wear area of the counterpart, Si<sub>3</sub>N<sub>4</sub> ball, increased from 2.016 mm<sup>2</sup> to 2.662 mm<sup>2</sup>. The increase in the hardness and tribological property were attributed to the grain refining strengthening.
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