Microstructure and wear resistance of in-situ TiC reinforced AlCoCrFeNi-based coatings by laser cladding

Abstract

High-entropy alloy (HEA) coatings of AlCoCrFeNi are being investigated as potential wear-resistance materials due to their excellent hardness and wear resistance. In this work, AlCoCrFeNi-based coatings were reinforced by in-situ TiC particles via laser cladding. The microstructure and wear resistance were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), and wear resistance tests. In addition, the hardness of oxidation TiC particles was analyzed by first principles calculations. The results show that the dominant phase of AlCoCrFeNi-based coatings is BCC phase. In-situ TiC particles present a flower-shaped morphology with Al2O3 core. Based on the calculated hardness, the hardness of TiC decreases with the increase of oxygen atoms in TiC. The hardness and wear resistance are improved considerably with the generation of the in-situ TiC particles. The AlCoCrFeNi-20% TiC coating exhibits the best wear resistance with an average hardness of 684.4 HV0.3, and the main wear mechanism is abrasive wear.