In Situ Formation of TiC Reinforced Intermetallic-Matrix Composite Layers Produced by Laser Cladding
Laser cladding technique was used to form Ni3(Si,Ti) intermetallic composite coating reinforced by in-situ formation TiC particles on Ni-based superalloy substrate. The experimental results showed that an excellent bonding between the coating and the substrate was ensured by a strong metallurgical interface. The clad coating was very well and free from cracks and pores. By means of scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD), the effect of Ti-C addition to the microstructure and microhardness of the coating was investigated. The microstructure of the coating was mainly composed of Ni(Si), Ni3(Si,Ti) and TiC. The average microhardness of the coating was improved with increasing the Ti-C content. The microhardness was up to 780Hv when Ti-C addition was 20 wt. pct, which was much greater than that of Ni-based superalloy substrate.
Wei Pan and Jianghong Gong
D. Fan et al., "In Situ Formation of TiC Reinforced Intermetallic-Matrix Composite Layers Produced by Laser Cladding", Key Engineering Materials, Vols. 336-338, pp. 1380-1382, 2007