*3.1. Macro Morphology*

Based on the selected experimental parameters in Table 2, a high entropy alloy laser cladding experiment was carried out. The macro morphology of the cladding layer under different specific energies is shown in Figure 3. It can be seen from Figure 3 that as the specific energy increases, the surface quality of the cladding layer changes significantly. In order to investigate the influence of specific energy on the cladding layer, the cross-sections of each high entropy alloy laser cladding layers are shown in Figure 4.

**Figure 3.** Surface morphology of high entropy alloy laser cladding layer under different specific energies. (**a**) 40.9 J/mm2; (**b**) 58.3 J/mm2; (**c**) 89.3 J/mm2.

During the laser cladding process, affected by the influence of surface tension and wetting, a parabolic morphology was formed during the rapid solidification process. It can be seen from Figure 4 that the specific energy of laser cladding has a significant impact on the cladding layer morphology, specifically related to the cladding layer morphology size, that is, the cladding layer reinforcement (H), width (W), and melting depth (h). The test results are shown in Table 3. The results show that the specific energy has an important effect on the volume of the molten pool, which is specifically expressed in the reinforcement, width, and melting depth. With the increase of specific

energy, the size of the molten pool will increase accordingly. The penetration and width of the molten pool increase with higher specific energy, while the reinforcement does not show any regularity with higher specific energy.

**Figure 4.** Transverse section of the high entropy alloy laser cladding layer under different specific energies. (**a**) 40.9 J/mm2; (**b**) 58.3 J/mm2; (**c**) 89.3 J/mm2.


**Table 3.** The size of the cladding layer under different specific energy.
