Effect of process parameters on the microstructure and properties of laser-clad FeNiCoCrTi0.5 high-entropy alloy coating

摘要

FeNiCoCrTi0.5 coatings with different process parameters were fabricated by laser cladding. The macro-morphology, phase, micro-structure, hardness, and wear resistance of each coating were studied. The smoothness and dilution rate of the FeNiCoCrTi0.5 coating generally increased with the increase of specific energy (E-s), which is the laser irradiation energy received by a unit area. FeNiCoCrTi0.5 coatings at different parameters had bcc, fcc, and Ti-rich phases as well as equiaxed, dendritic, and columnar structures. When E-s increased, the size of each structure increased and the distribution area of the columnar and dendritic structures changed. The prepared FeNiCoCrTi0.5 coating with the E-s of 72.22 J center dot mm(-2) had the highest hardness and the best wear resistance, the highest hardness of the coating reached HV 498.37, which is twice the substrate hardness. The average hardness of the FeNiCoCrTi0.5 coating with the E-s of 72.22 J center dot mm(-2) was 15.8% higher than the lowest average hardness of the coating with the E-s of 108.33 J center dot mm(-2). The worn surface morphologies indicate that the FeNiCoCrTi0.5 coatings exhibited abrasive wear.