Oxidation behavior of laser cladded Ni-Si-Ti-C coatings at 1100 °C

Abstract

Waspaloy is a typical Ni-based superalloy that widely used for flue gas turbine blades, and its strengthening phase is Ni3(Al,Ti). Laser cladding is one of the most effective methods for repairing damaged gas turbine blades. TiC particulate reinforced Ni3(Si,Ti) intermetallic matrix composites (IMC) were laser cladded on Waspaloy using Ni-Si-Ti-C powder. The oxidation tests were performed at 1100 °C for 48 h and 95 h in air. The specimens before and after oxidation tests were studied using scanning electron microscopy (SEM), X-ray diffraction (XRD), and electron probe microanalysis (EPMA). Based on SEM and XRD results, the mechanisms of oxidation for the coatings were discussed.Waspaloy is a typical Ni-based superalloy that widely used for flue gas turbine blades, and its strengthening phase is Ni3(Al,Ti). Laser cladding is one of the most effective methods for repairing damaged gas turbine blades. TiC particulate reinforced Ni3(Si,Ti) intermetallic matrix composites (IMC) were laser cladded on Waspaloy using Ni-Si-Ti-C powder. The oxidation tests were performed at 1100 °C for 48 h and 95 h in air. The specimens before and after oxidation tests were studied using scanning electron microscopy (SEM), X-ray diffraction (XRD), and electron probe microanalysis (EPMA). Based on SEM and XRD results, the mechanisms of oxidation for the coatings were discussed.