Investigations of laser cladding TiC-Ti-Al coatings on γ-TiAl intermetallic alloy

TiC-Ti-Al alloy powders were prepared on the surface of Ti-Al alloy. TiC reinforced TiAl matrix composite coatings is synthesized by laser cladding. The microstructure were observed by optical microscope (OM) and scanning electron microscopy (SEM). X-ray diffraction (XRD) and X-ray energy dispersive spectroscopy (EDS) were employed to analysis the phases composition of coating. The changes of micro-hardness before and after laser processing were tested respectively. The results revealed that with the increase of laser scan-rate, the morphology of reinforced TiC homogeneously dispersed in TiAl matrix was changed into short-bar and particle shape from dendritic TiC. Meanwhile, the micro-hardness also increases but the thickness of the coating decreases.