Laser melted TiC reinforced nickel aluminide matrix in situ composites

Abstract

Titanium carbide reinforced nickel aluminide matrix in situ composites were produced using a newly patented laser melting furnace. Microstructure of the laser melted TiC/(Ni 3Al–NiAl) in situ composites was characterized by optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and transmission electron microscopy (TEM). Results showed that the constituent phases in the laser melted in situ composites are TiC, Ni 3Al and NiAl. Volume fraction of TiC and NiAl increase with increasing content of titanium and carbon. The growth morphology of the reinforcing TiC carbide has typically faceted features, indicating that the lateral growth mechanism is still predominant growth mode under rapid solidification conditions.